From willamette-fcst at listsmart.osl.state.or.us Fri Sep 1 11:57:33 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 1 Sep 2017 18:57:33 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT FRI SEP 1, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A building upper-level ridge will keep mixing suppressed today. Meanwhile, a strengthening surface thermal trough, along the coast, will maintain offshore flow. Hot surface temperatures, low humidity, and increasing wind speeds will likely combine to put the valley into State Fire Marshal Burn-Ban Conditions this afternoon. TODAY'S FORECAST: Sunny, hot, and breezy. Salem's high temperature today will be near 96?F (average is 80?F). Relative humidity: Dropping to near 30% by 2 p.m. Surface winds: N 10-15 mph. Transport winds: NE 15-20 mph this afternoon. Mixing height: Near 2000 feet at midday; only rising to 2500 feet by 5 p.m. Salem's sunset tonight: 7:48 p.m. (Salem Airport data for Thursday, August 31st: High 86?F; Rainfall: .00") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: Temperatures will climb to around 100?F Saturday through Tuesday. The National Weather Service has issued a "Heat Advisory" for the entire Willamette Valley from 2 p.m. Saturday until 10 p.m. Tuesday. In addition, a developing southerly flow aloft will likely transport wildfire smoke, from fires across SW Oregon and northern California, back over NW Oregon. The axis of the strong upper-level ridge is expected to shift eastward, to over eastern Oregon, on Wednesday and progress to over the Rockies by Friday. That will turn transport winds onshore and initiate a cooling trend. However, SE-S flow aloft will transport increasing amounts of moisture and unstable air northward over Oregon. Thundershower development may extend as far north as NW Oregon as soon as Wednesday evening, with a high probability of showers and thundershowers Thursday and Friday. That may signal a major change to what has been a very dry weather pattern. It is too soon to tell if this weather pattern change will create burning opportunities next week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_Pete.doc Type: application/msword Size: 37376 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 1 08:56:50 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 1 Sep 2017 15:56:50 +0000 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT FRI SEP 1, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A building upper-level ridge will greatly suppress mixing today, as a surface thermal trough builds northward along the coast. Hot surface temperatures, low humidity, and increasing offshore flow will likely combine to put the valley into State Fire Marshal Burn-Ban Conditions later this afternoon. TODAY'S FORECAST: Sunny, hot, and breezy. Salem's high temperature today will be near 96?F (average is 80?F). Relative humidity: Dropping to 45% by 11 a.m. and to 30% by 2 p.m. Surface winds: N 5-10 mph this morning; N 10-15 mph this afternoon. Transport winds: NE 10-15 mph this morning; NE 15-20 mph this afternoon. Mixing height: Only rising to 2500 feet by 5 p.m. Salem's sunset tonight: 7:48 p.m. (Salem Airport data for Thursday, August 31st: High 86?F; Rainfall: .00") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: Temperatures will climb to around 100?F Saturday through Tuesday. In addition, a developing southerly flow aloft will likely force wildfire smoke back over the region by Sunday. Increasing southerly flow aloft may transport enough moisture and instability northward for thunderstorm development by the middle of next week, as temperatures slowly begin to moderate. It is too soon to tell if the cooling trend will create burning opportunities. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 36864 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 5 08:38:43 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 5 Sep 2017 15:38:43 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 5, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT TUE SEP 5, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: An upper-level ridge is trapped over eastern Oregon, creating S flow aloft and offshore flow out of the Columbia Gorge and Cascade passes. Regional wildfire smoke had become trapped in the Willamette Valley, producing smoggy conditions that will keep the air quality degraded throughout today. Temperatures remain well above seasonal averages, but sunlight filtered by smoky skies will keep the Silverton Hills near 90?F. Mixing will not develop very well today with the offshore gradients, and field burning opportunities simply will not develop. TODAY'S FORECAST: Smog becoming Hot with Smoke Clouds. Salem's high temperature today will be near 90?F (average is 80?F). Relative humidity: Below 60% by 9 a.m. and nearing 35% by 5 p.m. Surface winds: Variable < 5 mph all day. Transport winds: S 5-10 mph this morning, becoming S-SW 5-10 mph this afternoon. Mixing height: Rising to 2000 feet by 5 p.m. Salem's sunset tonight: 7:41 p.m. (Salem Airport data for Monday, September 4th: High 92?F; Rainfall: .00") (Maximum Ventilation Index expected today: 20) EXTENDED DISCUSSION: The weather pattern remains unfavorable for field burning through Wednesday, as the upper-level ridge slowly breaks down and moves into Idaho. S flow aloft persists through the afternoon, with restricted mixing, but the offshore flow will weaken and flat gradients will develop overnight. Thursday morning will see the transition back to favorable weather arrive, as 2 weak upper-level disturbances move in from the Pacific Ocean, cooling the atmosphere and mixing out the lingering wildfire smoke. Onshore flow will slowly return to the Willamette Valley, with W-SW flow aloft, and partly cloudy skies may form in the afternoon hours over the Cascades. The timing of this improvement will determine whether field burning opportunities arrive before a weak marine push Thursday evening. Friday morning will see marine air warm & mix out quickly, as onshore flow builds with W flow aloft. A strong marine push will move into the Silverton Hills Friday afternoon, and could provide even better conditions for field burning ahead of the weekend. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 5 11:40:58 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 5 Sep 2017 18:40:58 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 5, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT TUE SEP 5, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: An upper-level ridge is trapped over eastern Oregon, creating S flow aloft and offshore flow out of the Columbia Gorge and Cascade passes. Regional wildfire smoke had become trapped in the Willamette Valley, producing smoggy conditions that will keep the air quality degraded throughout today. Temperatures remain well above seasonal averages, but sunlight filtered by smoky skies will keep the Silverton Hills near 90?F. Mixing will not develop very well today with the offshore gradients, and field burning opportunities simply will not develop. TODAY'S FORECAST: Smog becoming Hot with Smoke Clouds. Salem's high temperature today will be near 90?F (average is 80?F). Relative humidity: Below 50% now and nearing 35% by 5 p.m. Surface winds: Variable < 5 mph all day. Transport winds: S 5-10 mph now, becoming S-SW 5-10 mph this afternoon. Mixing height: Rising to 2000 feet by 5 p.m. Salem's sunset tonight: 7:41 p.m. (Salem Airport data for Monday, September 4th: High 92?F; Rainfall: .00") (Maximum Ventilation Index expected today: 20) EXTENDED DISCUSSION: The weather pattern remains unfavorable for field burning through Wednesday, as the upper-level ridge slowly breaks down and moves into Idaho. S flow aloft persists through the afternoon, with restricted mixing, but the offshore flow will weaken and flat gradients will develop overnight. Thursday morning will see the transition back to favorable weather arrive, as 2 weak upper-level disturbances move in from the Pacific Ocean, cooling the atmosphere and mixing out the lingering wildfire smoke. Onshore flow will slowly return to the Willamette Valley, with W-SW flow aloft, and partly cloudy skies may form in the afternoon hours over the Cascades. The timing of this improvement will determine whether field burning opportunities arrive before a weak marine push Thursday evening. Friday morning will see marine air warm & mix out quickly, as onshore flow builds with W flow aloft. A strong marine push will move into the Silverton Hills Friday afternoon, and could provide even better conditions for field burning ahead of the weekend. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 6 08:56:24 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 6 Sep 2017 15:56:24 +0000 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT WED SEP 6, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The strong upper-level ridge responsible for the recent heat-wave is slowly progressing eastward. In addition to wildfire smoke, increasing southerly flow aloft is transporting mid-level moisture northward over the state, from a decaying tropical system off the northern California coast. A surface thermal trough remains over the northern Willamette Valley this morning, with weak onshore flow from Newport to Salem and continued offshore flow from Redmond to Salem. The surface thermal trough is expected to push east of the Cascades this afternoon with increasing onshore flow helping the clear low-level wildfire smoke from the Willamette Valley. However, south-to-SE flow aloft will continue to force elevated wildfire smoke over the region, from SW Oregon and northern California, and enough moisture and instability for possible thunderstorm development. TODAY'S FORECAST: Mostly cloudy and smoky. Not as hot. Chance of afternoon and evening thunderstorms. Any rainfall totals likely less than .10" Salem's high temperature today will be near 86?F (average is 80?F). Relative humidity: Dropping to 50% around noon and to 45% by 5 p.m. Surface winds: S 5 mph this morning; SW 5 mph this afternoon. Transport winds: S 5 mph this morning; SW 5-10 mph this afternoon. Mixing height: Rising to 3000 feet by 2 p.m. and to 3500 feet by 5 p.m. Salem's sunset tonight: 7:39 p.m. (Salem Airport data for Tuesday, September 5th: High 89?F; Rainfall: .00") (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: An increasing unstable southerly flow aloft will continue on Thursday, as increasing onshore surface winds cool temperatures back close to average and purge low-level smoke from the valley. Once again, thundershower development is possible but with a greater chance of more significant rainfall, especially near the Cascades. The flow aloft may turn more southwesterly on Friday, which would push the threat of thunderstorms east of the Cascades. Continued onshore flow will hold temperatures near average and could create a burning opportunity. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 37376 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 6 11:57:14 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 6 Sep 2017 18:57:14 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT WED SEP 6, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level ridge is slowly progressing east of the area. Dense wildfire smoke is making for poor air quality and continues to restrict visibility across NW Oregon. S-SE flow aloft is also transporting elevated wildfire smoke, moisture, and increasingly unstable air northward over the state. A surface thermal trough is hanging on over NW Oregon but should shift east of the Cascades this afternoon. Developing onshore flow will slowly begin to clear low-level wildfire smoke from the Willamette Valley later today, but elevated smoke will persist at least through Thursday. Daytime heating should combine with increasing mid-level moisture to promote shower and thunderstorm development later today and tonight. Thunderstorms will initially produce more wind than rain but will moisten the air mass over time. TODAY'S FORECAST: Mostly cloudy and smoky. Not as hot. Increasing chance of showers and thundershowers through tonight. Possible rainfall totals up to .10" Salem's high temperature today will be near 86?F (average is 80?F). Relative humidity: Dropping to near 45% by 5 p.m. Surface winds: SW 5-10 mph...stronger gusts possible near showers. Transport winds: SW 10 mph...stronger and more variable near showers. Mixing height: Rising to 3000 feet by 2 p.m. and to 3500 feet by 5 p.m. Salem's sunset tonight: 7:39 p.m. (Salem Airport data for Tuesday, September 5th: High 89?F; Rainfall: .00") (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: An unstable southerly flow aloft will continue on Thursday, as increasing onshore surface winds cool temperatures back close to average and purge low-level smoke from the valley. Elevated wildfire smoke will remain, along with the threat of showers and thundershowers. The potential for wetting rains will also increase. The flow aloft may turn more southwesterly on Friday, which would push the threat of thunderstorms east of the Cascades. Continued onshore flow will hold temperatures near average and could create a burning opportunity. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 7 08:58:06 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 7 Sep 2017 15:58:06 +0000 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT WED SEP 6, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level ridge has progressed eastward, to over Idaho, with S-SE winds aloft transporting elevated wildfire smoke, moisture, and unstable air northward over Oregon. Showers and thundershowers were concentrated mainly over SW Oregon on Wednesday, but a few very light showers survived as far north as the central Willamette Valley. The air mass is becoming increasingly moist and unstable, so scattered showers and thundershowers will likely advance northward across the Willamette Valley today. At the surface, the thermal trough has stalled over central Oregon. Very weak onshore will slowly strengthen today, west of the Cascades, which will begin to clear low-level wildfire smoke from the Willamette Valley. However, elevated smoke will persist at least through Friday. Clouds and smoke will inhibit daytime heating, which will decrease, but not eliminate, the chance of afternoon and evening thunderstorm development. TODAY'S FORECAST: Mostly cloudy and smoky. Chance of showers and thundershowers. Rainfall totals likely less than a tenth of an inch. Salem's high temperature today will be near 82?F (average is 79?F). Relative humidity: Dropping to 55% by 5 p.m. Surface winds: NW-N 5-10 mph. Transport winds: NE 10 mph this morning; NW-N 10-15 mph this afternoon. Mixing height: Rising to only 3000 feet by 5 p.m. Salem's sunset tonight: 7:37 p.m. (Salem Airport data for Wednesday, September 6th: High 85?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: The state will continue to be under the influence of a weak upper-level trough on Friday, but winds aloft are expected to turn more southwesterly. That will reduce the threat of thunderstorms but maintain a chance of light showers. Increasing onshore flow will hold temperatures near average and could create a burning opportunity for dry fields. However, elevated wildfire smoke will likely persist over the region. An upper-level trough is predicted to move across southern British Columbia on Saturday, turning the winds aloft more westerly over Oregon. Strong onshore flow should significantly improve air quality. Temperatures will cool into the mid-70s with a slight chance of a light shower. A building upper-level ridge is expected to turn transport winds northerly on Sunday, and offshore early next week, as temperatures climb back to above normal. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 7 08:58:57 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 7 Sep 2017 15:58:57 +0000 Subject: [willamette-fcst] Corrected Date Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT THU SEP 7, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level ridge has progressed eastward, to over Idaho, with S-SE winds aloft transporting elevated wildfire smoke, moisture, and unstable air northward over Oregon. Showers and thundershowers were concentrated mainly over SW Oregon on Wednesday, but a few very light showers survived as far north as the central Willamette Valley. The air mass is becoming increasingly moist and unstable, so scattered showers and thundershowers will likely advance northward across the Willamette Valley today. At the surface, the thermal trough has stalled over central Oregon. Very weak onshore will slowly strengthen today, west of the Cascades, which will begin to clear low-level wildfire smoke from the Willamette Valley. However, elevated smoke will persist at least through Friday. Clouds and smoke will inhibit daytime heating, which will decrease, but not eliminate, the chance of afternoon and evening thunderstorm development. TODAY'S FORECAST: Mostly cloudy and smoky. Chance of showers and thundershowers. Rainfall totals likely less than a tenth of an inch. Salem's high temperature today will be near 82?F (average is 79?F). Relative humidity: Dropping to 55% by 5 p.m. Surface winds: NW-N 5-10 mph. Transport winds: NE 10 mph this morning; NW-N 10-15 mph this afternoon. Mixing height: Rising to only 3000 feet by 5 p.m. Salem's sunset tonight: 7:37 p.m. (Salem Airport data for Wednesday, September 6th: High 85?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: The state will continue to be under the influence of a weak upper-level trough on Friday, but winds aloft are expected to turn more southwesterly. That will reduce the threat of thunderstorms but maintain a chance of light showers. Increasing onshore flow will hold temperatures near average and could create a burning opportunity for dry fields. However, elevated wildfire smoke will likely persist over the region. An upper-level trough is predicted to move across southern British Columbia on Saturday, turning the winds aloft more westerly over Oregon. Strong onshore flow should significantly improve air quality. Temperatures will cool into the mid-70s with a slight chance of a light shower. A building upper-level ridge is expected to turn transport winds northerly on Sunday, and offshore early next week, as temperatures climb back to above normal. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 7 11:57:27 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 7 Sep 2017 18:57:27 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT THU SEP 7, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level ridge is centered over Idaho with S-SE winds aloft transporting elevated wildfire smoke, moisture, and unstable air northward over Oregon. The air mass is becoming increasingly moist and unstable. One line of very light showers moved northward, through the central Willamette Valley, this morning and is nearing the Portland area at midday. A stronger area of showers and thundershowers, currently over SW Oregon, will weaken as it pushes northward, into the Willamette Valley later this afternoon. At the surface, a thermal trough remains stalled over central Oregon. Very weak onshore flow, west of the Cascades, will slowly begin to clear low-level wildfire smoke from the Willamette Valley. However, SE winds aloft will maintain a feed of elevated smoke over the region at least through Friday. Clouds and smoke will inhibit daytime heating, decreasing but not eliminating the chance of afternoon and evening thunderstorm development. Rainfall amounts will generally be spotty and light across the valley, but thundershowers could produce brief downpours, along with gusty winds. TODAY'S FORECAST: Mostly cloudy and smoky. Chance of showers and thundershowers. Rainfall totals likely less than a tenth of an inch. Salem's high temperature today will be near 82?F (average is 79?F). Relative humidity: Dropping to 55% by 5 p.m. Surface winds: NW-N 5-10 mph. Transport winds: NW-N 10-15 mph. Mixing height: Rising to only 3000 feet by 5 p.m. Salem's sunset tonight: 7:37 p.m. (Salem Airport data for Wednesday, September 6th: High 85?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: The state will continue to be under the influence of a weak upper-level trough on Friday, but winds aloft are expected to turn more southwesterly. That will reduce the threat of thunderstorms but maintain a chance of light showers. Increasing onshore flow will hold temperatures near average and could create a burning opportunity for dry fields. However, elevated wildfire smoke will likely persist over the region. An upper-level trough is predicted to move across southern British Columbia on Saturday, turning the winds aloft more westerly over Oregon. Strong onshore flow should significantly improve air quality. Temperatures will cool into the mid-70s with a slight chance of a light shower. A building upper-level ridge is expected to turn transport winds northerly on Sunday, and offshore early next week, as temperatures climb back to above normal. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_Pete.doc Type: application/msword Size: 38400 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 8 08:55:39 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 8 Sep 2017 15:55:39 +0000 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:50 AM PDT FRI SEP 8, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: An upper-level trough, centered just off the northern California coast, sent a surge of showers and thundershowers northward into Oregon on Thursday. Strong thunderstorms produced large hail and brief downpours in the northern Cascades but only spotty very light rain in the Willamette Valley. A switch to weak onshore flow also began to clear wildfire smoke from the valley. An upper-level trough remains over the region today, but the system off the California coast has drifted southward and will be less of a factor. Winds aloft have veered from SSE to the SSW, which will stabilize the air mass and inhibit thunderstorm development. However, the air mass remains very moist, so light showers are possible. Mostly cloudy skies and increasing onshore flow will hold temperatures in the 70s today. Elevated wildfire smoke should continue to slowly clear from the region. High humidity and light winds will limit burning opportunities. TODAY'S FORECAST: Mostly cloudy, cooler, and humid. Not as smoky. A light shower is possible. Salem's high temperature today will be near 76?F (average is 79?F). Relative humidity: Dropping to 60% about 2 p.m. and to 55% by 5 p.m. Surface winds: Light this morning; NW 5-10 mph this afternoon. Transport winds: N 5 mph this morning; becoming NW 10 mph this afternoon. Mixing height: Rising to 3000 feet by 2 p.m. and to 4000 feet by 5 p.m. Salem's sunset tonight: 7:35 p.m. (Salem Airport data for Thursday, September 7th: High 86?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 40) EXTENDED DISCUSSION: An upper-level trough is predicted to move across southern British Columbia on Saturday, dragging a weak cold front across NW Oregon in the afternoon. Temperatures will cool into the low 70s with a chance of light showers late in the day. Strengthening onshore flow should further improve air quality. A building upper-level ridge is expected to turn transport winds northerly on Sunday, and offshore on Monday, as temperatures climb back to above normal. Wildfire smoke may get transported back into the region. Onshore flow could return as soon as Tuesday, initiating a cooling trend, improving air quality, and possibly creating burning opportunities. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 8 11:57:26 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 8 Sep 2017 18:57:26 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT FRI SEP 8, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The combination of onshore flow and moisture from a decaying tropical system, centered off the northern California coast, is maintaining cloudy skies over most of western Oregon. The California system is drifting southward and will be less of a factor today, in terms of shower development. SW winds aloft have stabilized the air mass slightly, so thunderstorms are not likely, but light afternoon showers can't be ruled out. Some breaks in the clouds are likely later today, but onshore flow will cap temperatures in the mid-70s. Mostly-elevated wildfire smoke should continue to slowly clear from the region. High humidity, light winds, the chance of showers, and gradient-stacking may all limit burning today. A PIBAL is scheduled for 2 p.m. TODAY'S FORECAST: Mostly cloudy, cooler, and humid. Not as smoky. A light shower is possible. Salem's high temperature today will be near 76?F (average is 79?F). Relative humidity: Dropping to 60% about 2 p.m. and to 55% by 5 p.m. Surface winds: Light; becoming NW 5-10 mph later today. Transport winds: Light; becoming NW 10 mph later today. Mixing height: Rising to 3000 feet by 2 p.m. and to 4000 feet by 5 p.m. Salem's sunset tonight: 7:35 p.m. (Salem Airport data for Thursday, September 7th: High 86?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 40) EXTENDED DISCUSSION: An upper-level trough is predicted to move across southern British Columbia on Saturday, dragging a weak cold front across NW Oregon in the afternoon. Temperatures will cool into the low 70s with a chance of light showers late in the day. Strengthening onshore flow should further improve air quality. A building upper-level ridge is expected to turn transport winds northerly on Sunday, and offshore on Monday, as temperatures climb back to above normal. Wildfire smoke may get transported back into the region. Onshore flow could return as soon as Tuesday, initiating a cooling trend, improving air quality, and possibly creating burning opportunities. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 11 08:41:04 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 11 Sep 2017 15:41:04 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 11, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT MON SEP 11, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A weak ridge aloft passes into Idaho today, increasing W flow gradually over time. High pressure east of the Cascades will weaken and move away, so current offshore gradients will improve; timing of this reversal will be the key factor, as the easterly winds are keeping temperatures above seasonal averages while helping fields dry out after recent rain events. The heating of the atmosphere from these winds will also limit the mixing that occurs with daytime heating, but a switch to onshore flow could also help improve ventilation. TODAY'S FORECAST: Partly Cloudy with Smoke Aloft. Salem's high temperature today will be near 87?F (average is 78?F). Relative humidity: Below 60% by 10 a.m. and nearing 30% by 5 p.m. Surface winds: N-NE 5-10 mph this morning, becoming N-NW 5-10 mph this afternoon and NW 8-12 mph this evening. Transport winds: NE 5-10 mph this morning, becoming N-NW 5-10 mph this afternoon and NW 10-15 mph this evening. Mixing height: Rising to 2000 feet by 12 p.m. and 3000 feet by 4 p.m. Salem's sunset tonight: 7:35 p.m. (Salem Airport data for Sunday, September 10th: High 82?F; Rainfall: .00") (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: Onshore flow increases Tuesday, as an upper-level disturbance shifts south across the Canadian border into Washington. Cooler temperatures with improved mixing should provide favorable ventilation for field burning opportunities, as gradients become positively stacked. A sea breeze in the late afternoon brings enough moisture to form evening clouds over the Silverton Hills. Wednesday, the progressive westerly flow continues and brings elevated moisture into the Willamette Valley. Cloud cover will limit heating and keep the humidity elevated, which may shorten any window for potential field burning operations. Clouds continue to stack against the Silverton Hills Wednesday night as an approaching storm system increases the onshore flow and generates drizzle and damp fog. The storm will move through with its Cold Front on Thursday, and isolated thundershowers may produce wetting rains across the Willamette Valley. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 11 11:46:12 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 11 Sep 2017 18:46:12 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 11, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:50 AM PDT MON SEP 11, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A weak ridge aloft passes into Idaho today, increasing W flow gradually over time. Offshore flow has begun to weaken, but more improvement is needed this afternoon to bring onshore flow into the Willamette Valley. Smoke has begun to creep out of the Columbia Gorge, but air quality will improve again as the mixing height rises this afternoon and onshore winds cut off the smoke sources in the Cascades. Any window for field burning today will come in the later afternoon, and will be brief as winds and gradients become favorable before mixing begins to decrease this evening. TODAY'S FORECAST: Partly Cloudy with Smoke Aloft. Salem's high temperature today will be near 89?F (average is 78?F). Relative humidity: Below 45% now and nearing 30% by 5 p.m. Surface winds: N 5-10 mph now, becoming N-NW 5-10 mph this afternoon and NW 5-10 mph this evening. Transport winds: N-NE 5-10 mph now, becoming N-NW 5-10 mph this afternoon and NW 10-15 mph this evening. Mixing height: Near 2000 feet currently and rising to 3000 feet by 5 p.m. Salem's sunset tonight: 7:35 p.m. (Salem Airport data for Sunday, September 10th: High 82?F; Rainfall: .00") (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: Onshore flow increases Tuesday, as an upper-level disturbance shifts south across the Canadian border into Washington. Cooler temperatures with improved mixing should provide favorable ventilation for field burning opportunities, as gradients become positively stacked. A sea breeze in the late afternoon brings enough moisture to form evening clouds over the Silverton Hills. Wednesday, the progressive westerly flow continues and brings elevated moisture into the Willamette Valley. Cloud cover will limit heating and keep the humidity elevated, which may shorten any window for potential field burning operations. Clouds continue to stack against the Silverton Hills Wednesday night as an approaching storm system increases the onshore flow and generates drizzle and damp fog. The storm will move through with its Cold Front on Thursday, and isolated thundershowers may produce wetting rains across the Willamette Valley. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 12 08:42:25 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 12 Sep 2017 15:42:25 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 12, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT TUE SEP 12, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The weather pattern transitions today, with progressive W flow aloft cooling the atmosphere and enhancing daytime mixing for better air quality. Onshore gradients have developed overnight, and are already positively-stacked. Northerly winds will turn W-NW by mid-day and with cooler air aloft, ventilation should be favorable for field burning opportunities shortly after mid-day, ahead of a weak marine push tonight. TODAY'S FORECAST: Partly Cloudy Salem's high temperature today will be near 85?F (average is 78?F). Relative humidity: Below 60% by 10 a.m. and nearing 40% by 5 p.m. Surface winds: N 5-10 mph this morning, becoming NW 5-10 mph by noon and W-NW 8-12 mph this afternoon. Transport winds: N 5-10 mph this morning, becoming N-NW 5-10 mph by noon and W-NW 10-15 mph this afternoon. Mixing height: Rising to 3000 feet by 12 p.m. and 4000 feet by 4 p.m. Salem's sunset tonight: 7:28 p.m. (Salem Airport data for Monday, September 11th: High 94?F; Rainfall: .00") (Maximum Ventilation Index expected today: 60) EXTENDED DISCUSSION: W flow aloft increases as an upper-level disturbance shifts out of Canada on Wednesday, with marine clouds just north of the Silverton Hills after sunrise. Daytime heating will produce another day of favorable mixing, with W-NW transport winds and positive gradients in the afternoon hours likely to create another field burning opportunity. A significant pattern shift occurs late Wednesday night and into Thursday, as the upper-level disturbance creates a weak frontal system near the Oregon coast. This feature will not have time to gather much moisture, so cloud cover will be limited with almost no rainfall. Onshore gradients, wind directions and mixing conditions will be favorable for field burning, but wind speeds may down-mix any smoke and could be a limiting factor. A weak upper-level ridge over the Pacific Ocean will keep the Willamette Valley under W-NW flow aloft with cooler air continuing to move in and promote mixing with daytime heating on Friday. Field burning opportunities could develop ahead of a strong marine push Friday afternoon. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs0912a.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs0912a.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 12 11:42:59 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 12 Sep 2017 18:42:59 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 12, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT TUE SEP 12, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The weather pattern transitions today, with progressive W flow aloft cooling the atmosphere and enhancing daytime mixing for better air quality. Gradients have strengthened considerably with morning heating, and should be positively stacked across the mid-valley shortly. N-NW transport flow is present over the northern Willamette Valley, and rapid heating is allowing the atmosphere to ventilate to further improve air quality. The 1 p.m. PIBAL should provide the final confirmation needed to begin potential field burning in favored areas. TODAY'S FORECAST: Partly Cloudy. Salem's high temperature today will be near 85?F (average is 78?F). Relative humidity: 40% currently and nearing 30% by 5 p.m. Surface winds: NW 5-10 mph currently, becoming W-NW 8-12 mph this afternoon. Transport winds: N-NW 5-10 mph currently, becoming W-NW 10-15 mph this afternoon. Mixing height: 3000 feet now and rising to 4500 feet by 5 p.m. Salem's sunset tonight: 7:28 p.m. (Salem Airport data for Monday, September 11th: High 94?F; Rainfall: .00") (Maximum Ventilation Index expected today: 68) EXTENDED DISCUSSION: W flow aloft increases as an upper-level disturbance shifts out of Canada on Wednesday, with marine clouds just north of the Silverton Hills after sunrise. Daytime heating will produce another day of favorable mixing, with W-NW transport winds and positive gradients in the afternoon hours likely to create another field burning opportunity. A significant pattern shift occurs late Wednesday night and into Thursday, as the upper-level disturbance creates a weak frontal system near the Oregon coast. This feature will not have time to gather much moisture, so cloud cover will be limited with almost no rainfall. Onshore gradients, wind directions and mixing conditions will be favorable for field burning, but wind speeds may down-mix any smoke and could be a limiting factor. A weak upper-level ridge over the Pacific Ocean will keep the Willamette Valley under W-NW flow aloft with cooler air continuing to move in and promote mixing with daytime heating on Friday. Field burning opportunities could develop ahead of a strong marine push Friday afternoon. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 13 08:42:55 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 13 Sep 2017 15:42:55 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 13, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT TUE SEP 12, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Onshore flow will build continuously today, with W flow aloft ahead of an upper-level disturbance near the Canadian border. Gradients will become positively stacked this afternoon, with all other weather parameters favorable for field burning operations. Temperatures will remain near seasonal averages. TODAY'S FORECAST: Partly Cloudy. Salem's high temperature today will be near 76?F (average is 78?F). Relative humidity: Below 60% by 11 a.m. and nearing 35% by 5 p.m. Surface winds: N-NW 5-10 mph this morning, becoming NW 7-12 mph this afternoon. Transport winds: NW 5-10 mph this morning, becoming W-NW 10-15 mph this afternoon. Mixing height: Rising to 3000 feet by 1 p.m. and 4500 feet by 5 p.m. Salem's sunset tonight: 7:26 p.m. (Salem Airport data for Tuesday, September 12th: High 91?F; Rainfall: .00") (Maximum Ventilation Index expected today: 68) EXTENDED DISCUSSION: The upper-level disturbance will sweep southeasterly across Oregon on Thursday, ahead of a frontal system that forms along the Oregon coast and will quickly track east. Mixing, onshore gradients and wind direction will all be favorable as this feature passes without much rainfall, but breezy winds may preclude any field burning opportunities. An upper-level ridge near the Canadian coast will maintain cool, NW flow aloft with continued gradients on Friday, which could result in another field burning window ahead of the weekend. Temperatures will remain slightly below seasonal averages on Saturday. A weak upper-level disturbance will rocket across western Oregon, creating W-SW flow aloft with enhanced mixing. Sunday marks a seasonal pivot point, as a strong upper-level disturbance drives a storm system towards the Pacific Northwest. Excellent mixing ahead of a Cold Front and wetting rains Sunday afternoon will be followed by scattered rain showers throughout Monday. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 13 11:40:08 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 13 Sep 2017 18:40:08 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 13, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT TUE SEP 12, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Onshore flow builds slowly, with W flow aloft ahead of an upper-level disturbance near the Canadian border. Steady north surface winds have slowed the heating, but overall onshore gradients with NW transport will help lift smoke up & out of the Silverton Hills this afternoon. Continued heating will help achieve better gradients and turn surface flow more NW after 2 p.m. as mixing heights approach 4,500 feet later today. TODAY'S FORECAST: Partly Cloudy. Salem's high temperature today will be near 75?F (average is 78?F). Relative humidity: Below 50% now and nearing 35% by 5 p.m. Surface winds: N-NW 5-10 mph currently, becoming NW 7-12 mph this afternoon. Transport winds: NW 5-10 mph currently, becoming W-NW 10-15 mph this afternoon. Mixing height: Rising to 3000 feet by 1 p.m. and 4500 feet by 5 p.m. Salem's sunset tonight: 7:26 p.m. (Salem Airport data for Tuesday, September 12th: High 91?F; Rainfall: .00") (Maximum Ventilation Index expected today: 68) EXTENDED DISCUSSION: The upper-level disturbance will sweep southeasterly across Oregon on Thursday, ahead of a frontal system that forms along the Oregon coast and will quickly track east. Mixing, onshore gradients and wind direction will all be favorable as this feature passes without much rainfall, but breezy winds may preclude any field burning opportunities. On Friday, an upper-level ridge near the Canadian coast will maintain cool, NW flow aloft with continued onshore gradients, which could result in another field burning window ahead of the weekend. Temperatures will remain slightly below seasonal averages on Saturday. A weak upper-level disturbance will rocket across western Oregon, creating W-SW flow aloft with enhanced mixing. Sunday marks a seasonal pivot point, as a strong upper-level disturbance drives a storm system towards the Pacific Northwest. SW flow ahead of a Cold Front and thundershowers Sunday evening will be followed by scattered rain showers throughout Monday. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 14 08:59:01 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 14 Sep 2017 15:59:01 +0000 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT THU SEP 14, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from 11 a.m. until 2 p.m. with a 50-acre limit. WEATHER DISCUSSION: A dry upper-level trough will bring seasonal temperatures today under partly cloudy skies. Cool air aloft will provide excellent mixing. Weak onshore gradients have some negative-stacking this morning but should become balanced this afternoon. However, transport winds are predicted to remain mostly northerly and will be the limiting factor for burning. TODAY'S FORECAST: Partly cloudy and mild. Salem's high temperature today will be near 76?F (average is 78?F). Relative humidity: Dropping to 50% by 11 a.m. and to 30% by 5 p.m. Surface winds: N 5 mph this morning; NNW 5-10 mph this afternoon. Transport winds: N 5-10 mph this morning; NNW 8-13 mph this afternoon. Mixing height: Rising to 3000 feet by 11 a.m. and to 6000 feet by 5 p.m. Salem's sunset tonight: 7:24 p.m. (Salem Airport data for Wednesday, September 13th: High 77?F; Rainfall: .00") (Maximum Ventilation Index expected today: 40) EXTENDED DISCUSSION: A weak and transitory upper-level ridge will clear skies on Friday with afternoon temperatures warming to near 80?F. The air aloft will remain cool enough for good daytime mixing with northerly transport winds turning northeasterly Friday night. Low-level winds are expected to veer from NE to SE on Saturday, as the weak upper-level ridge breaks down. Increasing westerly flow aloft should push some clouds into the area by Saturday afternoon. A major change in the weather pattern is expected on Sunday, as the first fall-like storm of the season gets pushed onshore. Ahead of the cold front, low-level winds will increase and veer to the S-SW Sunday morning. Light rain is predicted to spread across the Willamette Valley Sunday afternoon. The timing of this system does not appear optimal for field-burning, as it may come in too early in the day. An even stronger weather system is expected to bring more significant rain on Monday with temperatures cooling into the low-60s. Rainfall totals may exceed one-half inch. Cool and showery weather is expected to extend at least through the middle of next week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 14 11:57:51 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 14 Sep 2017 18:57:51 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT THU SEP 14, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from now until 2 p.m. with a 50-acre limit. WEATHER DISCUSSION: A dry upper-level trough will slowly exit the region this afternoon with a dry NW flow aloft clearing skies. Cool air aloft will provide excellent mixing. Weak onshore gradients are nearly balanced and should become positively-stacked this afternoon. However, transport winds may stay mostly northerly, potentially limiting burning opportunities. The first PIBAL is scheduled for noon. TODAY'S FORECAST: Mostly sunny with mild temperatures. Salem's high temperature today will be near 76?F (average is 78?F). Relative humidity: Dropping to 30% by 5 p.m. Surface winds: NNW-N 5-10 mph. Transport winds: NNW 8-15 mph. Mixing height: Rising to 6000 feet by 5 p.m. Salem's sunset tonight: 7:24 p.m. (Salem Airport data for Wednesday, September 13th: High 77?F; Rainfall: .00") (Maximum Ventilation Index expected today: 80) EXTENDED DISCUSSION: A weak upper-level ridge will bring sunny and warmer weather on Friday with high temperatures near 80?F. The air aloft will remain cool enough for good daytime mixing with mostly northerly transport winds. On Saturday, transport winds should start out weakly offshore. However, the latest computer guidance shows a strengthening westerly flow aloft turning transport winds northwesterly Saturday afternoon. That could create a burn opportunity and will need to be closely watched. A major change in the weather pattern is expected on Sunday, as the first fall-like storm of the season gets pushed onshore. Low-level winds will increase and veer to the S-SW Sunday morning. A cold front is predicted to spread light rain across the Willamette Valley Sunday afternoon. Right now, it appears that this system will arrive too soon in the day to allow for a burning opportunity, but its timing will need to be closely watched. A stronger weather system is expected to bring more significant rain on Monday with temperatures cooling into the low-60s. Rainfall totals may exceed one-half inch. Cool and showery weather is expected to extend at least through the middle of next week. Long-range computer models are indicating a return to a drier weather pattern the final week of the month. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 15 08:59:12 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 15 Sep 2017 15:59:12 +0000 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT FRI SEP 15, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Weak offshore flow, in the wake of yesterday's dry upper-level trough, brought wildfire smoke back into sections of the valley. Pressure gradients remain slightly offshore this morning, and valley nephelometer readings are somewhat elevated, especially along the Cascade foothills and near Portland. A weak upper-level ridge will provide sunshine and seasonably warm temperatures today. The air aloft has warmed since Thursday but is still cool enough for good afternoon mixing. Surface pressure gradients should turn weakly onshore this afternoon, which will help to clear the low-level wildfire smoke from the valley and may create a limited burning opportunity. TODAY'S FORECAST: Sunny and warm. Areas of wildfire smoke, mainly this morning. Salem's high temperature today will be near 80?F (average is 77?F). Relative humidity: Dropping to 50% by noon and to near 30% by 5 p.m. Surface winds: Light this morning; N 5-10 mph this afternoon. Transport winds: NE 5-10 mph this morning; NNW 8-13 mph this afternoon. Mixing height: Rising to 3000 feet by 1 p.m. and to 5000 feet by 5 p.m. Salem's sunset tonight: 7:22 p.m. (Salem Airport data for Thursday, September 14th: High 78?F; Rainfall: .00") (Maximum Ventilation Index expected today: 65) EXTENDED DISCUSSION: Friday night through Saturday, offshore flow will likely transport wildfire smoke, from the Cascades, back into the valley. Otherwise, skies will be partly cloudy with continued seasonably warm temperatures. A strengthening westerly flow aloft should force a weak surface thermal trough east of the valley Saturday night, with a switch to onshore flow improving air quality. A major change in the weather pattern is expected on Sunday, as the first fall-like storm of the season gets pushed onshore. Low-level winds will increase and veer to the S-SW Sunday morning. A cold front is predicted to spread light rain across the Willamette Valley Sunday afternoon. The timing of this system has been slowed down, so there may be a midday burning opportunity, before rain spreads across the valley in the afternoon. A stronger weather system is expected to bring more significant rain on Monday with temperatures cooling into the low-60s. Rainfall totals may exceed one-half inch. Cool and wet weather is expected to extend through most of next week. Long-range computer models are indicating a return to a drier weather pattern for the final week of the month. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 15 11:51:24 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 15 Sep 2017 18:51:24 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:50 AM PDT FRI SEP 15, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Weak offshore flow pushed wildfire smoke from the Cascades into sections of the valley overnight. Pressure gradients were reversing, to onshore, late this morning, but valley nephelometer readings remain elevated, especially along the Cascade foothills and near Portland. A weak upper-level ridge will bring sunshine and seasonably warm temperatures today. The air aloft is still cool enough for good afternoon mixing. Onshore flow should slightly increase this afternoon, helping to clear wildfire smoke from the valley and possibly creating a limited burning opportunity. A PIBAL is scheduled for 1 p.m. TODAY'S FORECAST: Sunny and warm. Some wildfire smoke, especially in the Cascade foothills. Salem's high temperature today will be near 80?F (average is 77?F). Relative humidity: Dropping to 50% by noon and to near 30% by 5 p.m. Surface winds: N 5-10 mph. Transport winds: N 8-13 mph. Mixing height: Rising to 3000 feet about 1 p.m. and to 5000 feet by 5 p.m. Salem's sunset tonight: 7:22 p.m. (Salem Airport data for Thursday, September 14th: High 78?F; Rainfall: .00") (Maximum Ventilation Index expected today: 65) EXTENDED DISCUSSION: Tonight through Saturday, offshore flow should transport smoke, from wildfires in the Cascades, back across the Willamette Valley. Otherwise, skies will be partly cloudy with seasonal temperatures. A strengthening westerly flow aloft should force a weak surface thermal trough east of the Cascades Saturday night, with a switch to onshore flow improving air quality. A major change in the weather pattern is expected on Sunday, with the first in a series of fall-like storms coming onshore. As a cold front approaches the coast, increasing low-level winds will veer to the S-SW Sunday morning. This may create a midday burning opportunity, before light rain spreads across the valley in the mid-to-late afternoon. Rainfall amounts near .10" are likely Sunday night. A stronger weather system will bring cooler temperatures and more significant rain Monday afternoon and night. Relatively cool and wet weather is expected to extend through most of next week. Rainfall totals in excess of an inch are likely. Long-range computer models are indicating a return to a drier weather pattern, beginning next Friday, which may last about a week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_Pete.doc Type: application/msword Size: 38400 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 18 08:38:34 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 18 Sep 2017 15:38:34 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 18, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT MON SEP 18, 2017 BURN ADVISORY: Agricultural burning is recommended to be limited to the hours of 8 a.m. to 5:30 p.m. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level disturbance is destabilizing the atmosphere, as a surface frontal system brings scattered showers and isolated thunderstorms across the Willamette Valley today. Wetting rains between 0.20-0.75 inches of rainfall have fallen in the last 24 hours, and an additional 0.67 inches are expected to fall today across Marion County. The heaviest showers will occur this afternoon and persist overnight. TODAY'S FORECAST: Windy with Thundershowers. Salem's high temperature today will be near 61?F (average is 77?F). Relative humidity: 70% or higher for the next 24 hours. Surface winds: S 10-15 mph this morning, becoming SW 13-18 mph this afternoon. Transport winds: W-SW 15-20 mph this morning, becoming SW 20-30 mph this afternoon. Mixing height: Above 5000 feet for the next 24 hours. Salem's sunset tonight: 7:16 p.m. (Salem Airport data for Sunday, September 17th: High 67?F; Rainfall: .22") (Maximum Ventilation Index expected today: 150) EXTENDED DISCUSSION: Fall weather continues with little to no change between Monday night and the arrival of the Autumnal Equinox on Friday morning, when the calendar "officially" marks the end of the 2017 summer. The jet stream will remain over southern Oregon, bringing polar air and stormy weather for the next several days. Cloudy skies with only brief periods of sunbreaks will limit any drying, though parched soil and stiff winds will help in a limited fashion. Occasional thundershowers with lingering rainfall will continue to dampen fields until a ridge develops and forces the jet stream back north of the Silverton Hills, but current weather models indicate unfavorable field burning conditions for the next 7-10 days. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 29696 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 18 11:43:48 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 18 Sep 2017 18:43:48 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 18, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT MON SEP 18, 2017 BURN ADVISORY: Agricultural burning is recommended to be limited to the hours of 8 a.m. to 5:30 p.m. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level disturbance is destabilizing the atmosphere, as a surface frontal system brings scattered showers and isolated thunderstorms across the Willamette Valley today. Strong thundershowers are moving through the Oregon coast towards the Silverton Hills, and will bring heavy showers, gusty winds & the possibility of small hail this afternoon. A waterspout was sighted near Netarts, Oregon and indicates that severe weather may impact western Oregon as this storm passes. TODAY'S FORECAST: Windy with Thundershowers. Small Hail is possible. Salem's high temperature today will be near 61?F (average is 77?F). Relative humidity: 70% or higher for the next 24 hours. Surface winds: S 10-15 mph this morning, becoming SW 13-18 mph this afternoon. Transport winds: W-SW 15-20 mph this morning, becoming SW 20-30 mph this afternoon. Mixing height: Above 5000 feet for the next 24 hours. Salem's sunset tonight: 7:16 p.m. (Salem Airport data for Sunday, September 17th: High 67?F; Rainfall: .22") (Maximum Ventilation Index expected today: 150) EXTENDED DISCUSSION: Fall weather continues with little to no change between Monday night and the arrival of the Autumnal Equinox on Friday morning, when the calendar "officially" marks the end of the 2017 summer. The jet stream will remain over southern Oregon, bringing polar air and stormy weather for the next several days. Cloudy skies with only brief periods of sunbreaks will limit any drying, though parched soil and stiff winds will help in a limited fashion. Occasional thundershowers with lingering rainfall will continue to dampen fields until a ridge develops and forces the jet stream back north of the Silverton Hills, but current weather models indicate unfavorable field burning conditions for the next 7-10 days. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 19 08:40:25 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 19 Sep 2017 15:40:25 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 19, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT TUE SEP 19, 2017 BURN ADVISORY: Agricultural burning is recommended to be limited to the hours of 8 a.m. to 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level disturbance remains over the Pacific Northwest, with scattered showers and isolated thundershowers in the Cascades. Approximately 0.91 inches fell in the last 24 hours in Salem, mostly before sunrise today. The Silverton Hills could see another 1.25-1.50 inches of rain fall before sunrise Wednesday. Small hail is possible with larger thunderstorms this afternoon. TODAY'S FORECAST: Windy with Thundershowers. Small Hail possible. Salem's high temperature today will be near 61?F (average is 76?F). Relative humidity: 60% or higher for the next 24 hours. Surface winds: S-SW 10-15 mph this morning, becoming SW 15-25 mph this afternoon. Transport winds: W 30 mph this morning, becoming W-SW 25-35 mph this afternoon. Mixing height: Above 5000 feet for the next 24 hours. Salem's sunset tonight: 7:14 p.m. (Salem Airport data for Sunday, September 18th: High 63?F; Rainfall: .91") (Maximum Ventilation Index expected today: 175) EXTENDED DISCUSSION: Fall weather continues with little to no change between Monday night and the arrival of the Autumnal Equinox on Friday morning, when the calendar "officially" marks the end of the 2017 summer. The jet stream will remain over southern Oregon, bringing polar air and stormy weather for the next several days. An upper-level ridge will slowly form over the Pacific, but cloud cover will continue to spill over it through the early weekend; this will limit drying until the ridge moves overhead early next week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 29696 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 19 11:43:16 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 19 Sep 2017 18:43:16 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 19, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT TUE SEP 19, 2017 BURN ADVISORY: Agricultural burning is recommended to be limited to the hours of 8 a.m. to 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level disturbance remains over the Pacific Northwest, with scattered showers and isolated thundershowers in the Cascades. A brief pause in showers will end soon, as more storms move into the Willamette Valley. The Silverton Hills could see another inch or more of rain fall before sunrise Wednesday. Small hail is possible with larger thunderstorms later this evening. TODAY'S FORECAST: Windy with Thundershowers. Small Hail possible. Salem's high temperature today will be near 61?F (average is 76?F). Relative humidity: 60% or higher for the next 24 hours. Surface winds: S-SW 10-15 mph this morning, becoming SW 15-25 mph this afternoon. Transport winds: W 30 mph this morning, becoming W-SW 25-35 mph this afternoon. Mixing height: Above 5000 feet for the next 24 hours. Salem's sunset tonight: 7:14 p.m. (Salem Airport data for Sunday, September 18th: High 63?F; Rainfall: .91") (Maximum Ventilation Index expected today: 175) EXTENDED DISCUSSION: Fall weather continues with little to no change before the arrival of the Autumnal Equinox on Thursday night, when the calendar "officially" marks the end of the 2017 summer. The jet stream will remain over southern Oregon, bringing polar air and stormy weather for the next several days, keeping temperatures well below seasonal averages. An upper-level ridge will slowly form over the Pacific, but cloud cover will continue to spill over it through the early weekend; this will limit drying until the ridge moves overhead early next week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 29696 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 20 08:46:22 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 20 Sep 2017 15:46:22 +0000 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT WED SEP 20, 2017 BURN ADVISORY: Recommended times for agricultural burning are from 8 a.m. until 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: An unseasonably strong and cold upper-level trough will maintain vigorous shower activity today with possible thundershowers. TODAY'S FORECAST: Showers. Chance of thundershowers. Rainfall totals .25" to .50". Salem's high temperature today will be near 62?F (average is 76?F). Relative humidity: Dropping to near 60% by 5 p.m. Surface winds: SW 10-15 mph this morning; NW 10-15 mph later this afternoon. Transport winds: SW 25 mph this morning; NW 15 mph later this afternoon. Mixing height: Rising to 3500 feet by 11 a.m. and to 5000 feet by 2 p.m. Salem's sunset tonight: 7:13 p.m. (Salem Airport data for Tuesday, September 19th: High 66?F; Rainfall: .95") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: Very cool weather will continue on Thursday but with decreasing shower activity. Rainfall totals should mostly be around .10" or less. A drier and more stable northerly flow aloft will clear skies on Friday, but temperatures will remain about 10 degrees below average. A building upper-level ridge will maintain mostly sunny skies and light NW winds over the weekend, which will give fields an opportunity to begin drying. Temperatures will progressively warm back to near average by Monday with winds turning mostly northerly. Winds may turn briefly offshore on Tuesday, which would further promote the drying of fields and help temperatures climb to above average. The upper-level ridge is predicted to shift east of the state by Wednesday. Increasing SW flow aloft will force a weak surface thermal trough east of the Cascades later next week, introducing onshore flow back into western Oregon. That transition should create an opportunity to burn any remaining fields. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 37376 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 20 11:53:56 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 20 Sep 2017 18:53:56 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:50 AM PDT WED SEP 20, 2017 BURN ADVISORY: Recommended times for agricultural burning are from now until 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: An unseasonably strong and cold upper-level trough will maintain vigorous shower activity today with possible thundershowers. Over one-third of an inch of rain has already fallen today at the Salem Airport, bringing the total this week to around two inches. TODAY'S FORECAST: Showers and cool. Chance of thundershowers. Rainfall totals near .50". Salem's high temperature today will be near 62?F (average is 76?F). Relative humidity: Dropping to near 60% by 5 p.m. Surface winds: SW 10-15 mph; becoming W 10-15 mph later this afternoon. Transport winds: SW 20-25 mph; becoming W 15 mph later this afternoon. Mixing height: Above 5000 feet. Salem's sunset tonight: 7:13 p.m. (Salem Airport data for Tuesday, September 19th: High 66?F; Rainfall: .95") (Maximum Ventilation Index expected today: 125) EXTENDED DISCUSSION: Unseasonably cool weather will continue on Thursday but with far less shower activity. Rainfall totals should mostly be around .10" or less. A drier and more stable northerly flow aloft will clear skies on Friday, but temperatures will remain about 10 degrees below average. A building upper-level ridge will bring mostly sunny skies and light NW winds over the weekend, allowing fields a drying opportunity. Temperatures will progressively warm back to near average, by Monday, with winds veering to northerly. Offshore flow is possible by Tuesday, which would promote further drying of fields and help temperatures climb to near 80?F. The upper-level ridge is expected to shift east of the state by Wednesday. Increasing SW flow aloft will introduce onshore flow back into western Oregon, late next week, likely allowing for the burning of remaining fields. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_Pete.doc Type: application/msword Size: 37376 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 21 08:54:18 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 21 Sep 2017 15:54:18 +0000 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:50 AM PDT THU SEP 21, 2017 BURN ADVISORY: Recommended times for agricultural burning are from 11 a.m. until 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: Vigorous showers dropped another two-thirds of an inch of rain at the Salem Airport on Wednesday. Rainfall since Sunday has been just over two-and-a-quarter inches. Salem's high temperature of 59?F, on Wednesday, was a record-cold maximum for the date (the previous record was 60?F in 1982). A cold upper-level trough will maintain unseasonably cool weather today but with far less shower activity. Additional rainfall totals should be less than a tenth of an inch. TODAY'S FORECAST: Patchy morning fog, then mostly cloudy and cool with a few showers. Salem's high temperature today will be near 62?F (average is 76?F). Relative humidity: Dropping to near 60% by 5 p.m. Surface winds: S 5-10 mph this morning; SW 5-10 mph later this afternoon. Transport winds: SW 5-10 mph this morning; W 5-10 mph later this afternoon. Mixing height: Rising to 3000 feet by noon and to 5000 feet by 5 p.m. Salem's sunset tonight: 7:11 p.m. (Salem Airport data for Wednesday, September 20th: High 59?F; Rainfall: .66") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: A drier and more stable northerly flow aloft will bring more sunshine on Friday, but temperatures will remain about 10 degrees below average. A slight chance showers will persist, especially in the Cascade foothills. A building upper-level ridge will bring partly to mostly sunny skies and light NW winds over the weekend, after areas of morning fog. That will allow fields to begin the drying process. Temperatures will progressively warm back to near average, by Monday, with light winds turning northerly. As the ridge strengthens over the region, winds should turn offshore on Tuesday, and perhaps Wednesday, which will promote further drying of fields and help temperatures climb to near 80?F. The upper-level ridge is expected to shift east of the state by Thursday. Increasing SW flow aloft will introduce onshore flow back into western Oregon, which should allow for the burning of remaining fields. A weak cold front is slated to bring back a threat of showers on Friday. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Pete.doc Type: application/msword Size: 37888 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 21 11:40:47 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 21 Sep 2017 18:40:47 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:40 AM PDT THU SEP 21, 2017 BURN ADVISORY: Recommended times for agricultural burning are from now until 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: A weakening upper-level trough will maintain unseasonably cool weather today but with far less shower activity. Additional rainfall totals should be less than a tenth of an inch. TODAY'S FORECAST: Mostly cloudy and cool with scattered light showers. Salem's high temperature today will be near 62?F (average is 76?F). Relative humidity: Dropping to near 60% by 5 p.m. Surface winds: S 10-15 mph; becoming SW 10-15 mph later this afternoon. Transport winds: SW 15 mph; becoming W 15 mph later this afternoon. Mixing height: Rising to 5000 feet by 5 p.m. Salem's sunset tonight: 7:11 p.m. (Salem Airport data for Wednesday, September 20th: High 59?F; Rainfall: .66") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: A more stable northerly flow aloft will bring drier weather and more sunshine on Friday, but temperatures will remain about 10 degrees below average. A slight chance showers will persist, especially along the Cascade foothills. A building upper-level ridge will bring partly to mostly sunny skies, after areas of morning fog, over the weekend. That will allow fields to begin the drying process. Temperatures will progressively warm back to near average, by Monday, with light NW winds turning northerly. As the upper-level ridge strengthens, winds should turn offshore Tuesday and Wednesday, which will promote further drying of fields and help temperatures climb to near 80?F. The thermal trough is expected to shift east of the Cascades on Thursday, with increasing SW flow aloft and onshore flow at the surface likely creating an afternoon burning opportunity. There may be another burning opportunity Friday afternoon, just ahead of a weak cold front. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_Pete.doc Type: application/msword Size: 37376 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 22 08:44:34 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 22 Sep 2017 15:44:34 +0000 Subject: [willamette-fcst] Willamette Valley Field Burning Forecast Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT FRI SEP 22, 2017 BURN ADVISORY: Recommended times for agricultural burning are from 11 a.m. until 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: Upper level ridge is nosing into British Columbia this morning with the upper low gradually moving to the east. Morning low clouds should clear later this morning but with residual cool air aloft and a moist ground, some afternoon clouds may build over the Cascades and provide a risk of some light showers. Moisture is unlikely in the Willamette Valley. Gradients will be weak today but favor a weak northerly flow. TODAY'S FORECAST: Morning clouds dissipating to mostly clear this afternoon. Salem's high temperature near 66F (average is 75F). Relative humidity: Will lower to near 50 percent around 4 p.m. Surface winds: Light and variable early becoming N at 5 - 10 later this morning and afternoon. Transport winds: Light and variable early becoming N at 5 - 10 mph later this morning and afternoon. Mixing height: Rising to 3000 ft by noon, rising to 4000 - 4500 ft by 3 p.m. Salem's sunset tonight: 7:09 p.m. (Salem Airport data for Thursday, Sep. 21: High 65?F; Rainfall: .01") (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: Upper level ridge gradually moves into the state over the weekend with the temperature warming into the lower 70s under plenty of fall sunshine. A weak disturbance rides over the ridge Monday and may provide a little more onshore flow but not likely any moisture. Ridge rebuilds on Tuesday and Wednesday and then gives way to a deeper trough approaching Thursday and Friday. Expect mostly northerly flow through the period except later next week when winds turn westerly to potentially provide a burn opportunity. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Nick Yonker ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills AM Forecast_Nick.doc Type: application/msword Size: 34816 bytes Desc: Silverton Hills AM Forecast_Nick.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 22 11:47:46 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 22 Sep 2017 18:47:46 +0000 Subject: [willamette-fcst] Willamette Valley Field Burning Forecast - Noon Update Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT FRI SEP 22, 2017 BURN ADVISORY: Recommended times for agricultural burning are from now until 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: Upper level ridge is nosing into British Columbia with the upper low gradually moving eastward. Morning low clouds are stubborn to dissipate but should clear early this afternoon. Residual cool air aloft and a moist ground may allow some afternoon clouds to build over the Cascades and provide a risk of some light showers. Moisture is unlikely in the Willamette Valley. Gradients remain weak but favor a northerly flow. TODAY'S FORECAST: Clouds dissipating to mostly clear this afternoon. Salem's high temperature near 66F (average is 75F). Relative humidity: Will lower to near 50 percent around 4 p.m. Surface winds: N at 5 - 10 mph. Transport winds: N at 5 - 10 mph. Mixing height: Rising to 3000 ft by noon, rising to 4000 - 4500 ft by 3 p.m. Salem's sunset tonight: 7:09 p.m. (Salem Airport data for Thursday, Sep. 21: High 65?F; Rainfall: .01") (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: Upper level ridge gradually moves into the state over the weekend but weakens some, allowing some weak onshore flow during afternoon hours. A weak disturbance rides over the ridge Monday and may provide a little more onshore flow but not likely any moisture. Ridge rebuilds on Tuesday and Wednesday and then gives way to a deeper trough approaching early Friday. Wind will likely turn westerly and potentially provide a burn opportunity. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Nick Yonker ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills PM Forecast_Nick.doc Type: application/msword Size: 34304 bytes Desc: Silverton Hills PM Forecast_Nick.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 25 08:41:09 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 25 Sep 2017 15:41:09 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 25, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT MON SEP 25, 2017 BURN ADVISORY: Recommend agricultural burning be limited to period between 2 p.m. and 5 p.m. today. Prep burning is not allowed. WEATHER DISCUSSION: The weather pattern today will be unfavorable for field burning activities. A weak upper-level ridge has let a surface frontal system sweep through this morning; while this feature is mostly clouds and little else, it will limit heating and keep humidity elevated over the next 24 hours. Clouds have spread over central Oregon too, so the gradients will not maintain steady onshore flow, either. High pressure develops over western Oregon this evening, helping clear out skies after sunset. TODAY'S FORECAST: Overcast becoming Mostly Cloudy later today. Salem's high temperature today will be near 67?F (average is 74?F). Relative humidity: 60% or higher for the next 24 hours. Surface winds: E-SE 5 mph this morning, becoming N-NW 5-10 mph this afternoon. Transport winds: N 5-10 mph this morning, becoming NW 10 mph this afternoon. Mixing height: Rising to 3000 feet by 2 p.m. and 3,500 feet by 5 p.m. Salem's sunset tonight: 7:03 p.m. (Salem Airport data for Sunday, September 24th: High 75?F; Rainfall: .00") (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: The upper-level ridge moves over the Oregon coast and lingers through mid-week, warming the atmosphere slowly and keeping skies clear to let in late September sunshine. Higher surface pressure develops over eastern Washington, turning gradient flow offshore across the Cascades for Tuesday and Wednesday. Temperatures will warm again above seasonal averages. This will help prime remaining fields by allowing continued drying after last week's rains and remnant moisture. A developing upper-level disturbance near Alaska begins to swing down towards Oregon Thursday, weakening the upper-level ridge and encouraging it to shift east into Idaho. Friday appears to be the long-awaited day, as flow aloft shifts to SW behind the ridge and a developing storm system near the Washington coast will enhance mixing and turn onshore flow S-SW in the afternoon hours. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 25 11:38:08 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 25 Sep 2017 18:38:08 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 25, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT MON SEP 25, 2017 BURN ADVISORY: Recommend agricultural burning be limited to period between 2 p.m. and 5 p.m. today. Prep burning is not allowed. WEATHER DISCUSSION: The weather pattern today will be unfavorable for field burning activities. Cloudy skies persist over the valley, with brief rain & drizzle earlier as a weak surface front passed by Salem. Temperatures have risen slowly, but humidity remains high and overall mixing heights are struggling to climb above 1,000 feet at this time without sunbreaks to increase the heating. Gradients are currently flat across the mid-valley, and may not improve at all if cloud cover persists. TODAY'S FORECAST: Overcast becoming Mostly Cloudy later today. Salem's high temperature today will be near 67?F (average is 74?F). Relative humidity: 60% or higher for the next 24 hours. Surface winds: Variable <5 mph this morning, becoming N-NW 5-10 mph this afternoon. Transport winds: N 5-10 mph this morning, becoming N-NW 5-10 mph this afternoon. Mixing height: Rising to 3000 feet by 3 p.m. Salem's sunset tonight: 7:03 p.m. (Salem Airport data for Sunday, September 24th: High 75?F; Rainfall: .00") (Maximum Ventilation Index expected today: 30) EXTENDED DISCUSSION: The upper-level ridge moves over the Oregon coast and lingers through mid-week, warming the atmosphere slowly and keeping skies clear to let in late September sunshine. A developing upper-level disturbance near Alaska begins to swing down towards Oregon Thursday, weakening the upper-level ridge and encouraging it to shift east into Idaho. Friday appears to be the long-awaited day, as flow aloft shifts to SW behind the ridge and a developing storm system near the Washington coast will enhance mixing and turn onshore flow S-SW after sunrise. Cloud cover will advance over western Oregon ahead of this feature, and conditions may develop by late morning to support field burning operations. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 26 08:44:58 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 26 Sep 2017 15:44:58 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 26, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT TUE SEP 26, 2017 BURN ADVISORY: Recommend agricultural burning be limited to period between 12 p.m. and 5 p.m. today. Prep burning is not allowed. WEATHER DISCUSSION: The upper-level ridge has moved closer to Oregon, turning flow aloft northerly and higher surface pressure east of the Cascades is creating offshore gradient flow. The atmosphere will warm and dry significantly, with only patchy fog in sheltered corners of the Willamette Valley. Mixing conditions will improve earlier today, but progress will remain limited overall as the ridge aloft caps rising air. TODAY'S FORECAST: Mostly Clear with Afternoon Haze. Salem's high temperature today will be near 77?F (average is 74?F). Relative humidity: Below 60% by 1 p.m. and near 40% by 5 p.m. Surface winds: N-NE 5-10 mph this morning, becoming N-NE 10-15 mph this afternoon. Transport winds: NE 10-15 mph this morning and afternoon. Mixing height: Rising to 3000 feet by 5 p.m. Salem's sunset tonight: 7:01 p.m. (Salem Airport data for Monday, September 25th: High 70?F; Rainfall: Trace Amounts) (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: The upper-level ridge remains dominant again Wednesday, with little changing other than temperatures climbing into the mid 80's throughout the Willamette Valley. The ridge will begin to weaken Wednesday night and drift into the Cascades before sunrise Thursday, and continue shifting east into Idaho by Thursday afternoon, ushering in a cooling period for Oregon. As it departs, an upper-level disturbance will descend from Alaska and create a storm system out over the Pacific Ocean. This storm will cross the Willamette Valley on Friday afternoon. Onshore gradients, a well-mixed atmosphere, and favorable wind direction should all be in place for late morning field burning activities ahead of afternoon showers. Cooler, unsettled weather is expected to linger through the upcoming weekend. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 26 11:43:47 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 26 Sep 2017 18:43:47 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 26, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT TUE SEP 26, 2017 BURN ADVISORY: Recommend agricultural burning be limited to period between 12 p.m. and 5 p.m. today. Prep burning is not allowed. WEATHER DISCUSSION: The upper-level ridge has moved closer to Oregon, turning flow aloft northerly and higher surface pressure east of the Cascades is creating offshore gradient flow. The atmosphere is warming steadily, but gradients remain offshore and are producing NE surface winds across the Willamette Valley. TODAY'S FORECAST: Mostly Clear with Afternoon Haze. Salem's high temperature today will be near 78?F (average is 74?F). Relative humidity: Below 60% now and near 40% by 5 p.m. Surface winds: N 5-10 mph now, becoming N-NE 10-15 mph this afternoon. Transport winds: NE 10-15 mph this morning and afternoon. Mixing height: Near 2500 feet now and rising to 3000 feet by 5 p.m. Salem's sunset tonight: 7:01 p.m. (Salem Airport data for Monday, September 25th: High 70?F; Rainfall: Trace Amounts) (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: The upper-level ridge remains dominant again Wednesday, with little changing other than temperatures climbing into the mid 80's throughout the region. The ridge will begin to weaken Wednesday night and drift into the Cascades before sunrise Thursday, and continue shifting east into Idaho by Thursday afternoon, ushering in a cooling period for Oregon. Weather models now indicate that a developing storm system south of Alaska will begin pushing south Thursday morning, turning flow SW in the afternoon hours ahead of a marine push Thursday night. If gradient flow turns around quickly enough on Thursday, this could provide afternoon field burning opportunities before the storm approaches Friday and threatens rainfall with breezy conditions. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 29696 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 27 08:46:31 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 27 Sep 2017 15:46:31 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 27, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT WED SEP 27, 2017 BURN ADVISORY: Recommend agricultural burning be limited to period between 12 p.m. and 5 p.m. today. Prep burning is not allowed. WEATHER DISCUSSION: The upper-level ridge has moved into the Oregon coast, and will bring warmest temperatures today as flow aloft becomes variable and offshore gradients reach their strongest point for the week. Mixing conditions will again see limited development with the ridge moving over the Willamette Valley this afternoon. Offshore gradients will slowly weaken this evening as the upper-level ridge passes into the Cascades and transport winds become southerly overnight. TODAY'S FORECAST: Sunny and Very Warm with Haze. Salem's high temperature today will be near 84?F (average is 73?F). Relative humidity: Below 60% by 10 a.m. and near 30% by 5 p.m. Surface winds: N-NE 5-10 mph this morning and afternoon. Transport winds: NE 5-10 mph this morning and afternoon. Mixing height: Rising to 2500 feet by 5 p.m. Salem's sunset tonight: 6:59 p.m. (Salem Airport data for Tuesday, September 26th: High 79?F; Rainfall: .00") (Maximum Ventilation Index expected today: 25) EXTENDED DISCUSSION: Flow across the Willamette Valley shifts significantly on Thursday, as the upper-level ridge exits rapidly to the east. S-SW transport winds with gradients turning onshore will bring an afternoon sea breeze ahead of a marine push Thursday night, and should allow field burning opportunities with excellent smoke ventilation. An upper-level disturbance over the Pacific Ocean will spread cloud cover across Oregon and a storm system will bring wetting rains on Friday afternoon; temperatures will drop nearly 20?F compared to Thursday as polar air pours into the region. The atmosphere will remain unstable with cloud cover and scattered showers through the weekend, as temperatures remain below seasonal averages for the upcoming week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 27 11:35:57 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 27 Sep 2017 18:35:57 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 27, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT WED SEP 27, 2017 BURN ADVISORY: Recommend agricultural burning be limited to period between 12 p.m. and 5 p.m. today. Prep burning is not allowed. WEATHER DISCUSSION: The upper-level ridge has moved into the Oregon coast, and will bring warmest temperatures today as flow aloft becomes variable and offshore gradients reach their strongest point for the week. Mixing conditions will again see limited development with the ridge moving over the Willamette Valley this afternoon. Offshore gradients will slowly weaken this evening as the upper-level ridge passes into the Cascades and transport winds become southerly overnight. TODAY'S FORECAST: Sunny and Very Warm with Haze. Salem's high temperature today will be near 84?F (average is 73?F). Relative humidity: Below 60% by 10 a.m. and near 30% by 5 p.m. Surface winds: N-NE 5-10 mph this morning and afternoon. Transport winds: NE 5-10 mph this morning and afternoon. Mixing height: Rising to 2500 feet by 5 p.m. Salem's sunset tonight: 6:59 p.m. (Salem Airport data for Tuesday, September 26th: High 79?F; Rainfall: .00") (Maximum Ventilation Index expected today: 25) EXTENDED DISCUSSION: Flow across the Willamette Valley shifts significantly on Thursday, as the upper-level ridge exits rapidly to the east. S-SW transport winds with gradients turning onshore will bring an afternoon sea breeze ahead of a marine push Thursday night, and should allow field burning opportunities with excellent smoke ventilation. An upper-level disturbance over the Pacific Ocean will spread cloud cover across Oregon and a storm system will bring wetting rains on Friday afternoon; temperatures will drop nearly 20?F compared to Thursday as polar air pours into the region. The atmosphere will remain unstable with cloud cover and scattered showers through the weekend, as temperatures remain below seasonal averages for the upcoming week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 29696 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 28 08:40:12 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 28 Sep 2017 15:40:12 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 28, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT THU SEP 28, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The upper-level ridge has weakened and shifted east of the Cascades, turning flow aloft southerly overnight and SW later today as it enters Idaho. Field burning opportunities are likely to appear mid-to-late this afternoon, as a developing storm system over the Pacific Ocean quickly turns flow onshore, and mixing improves steadily ahead of a marine push this evening. Cloud cover will slowly increase in the afternoon and evening hours as the storm approaches western Oregon. TODAY'S FORECAST: Increasing Clouds. Salem's high temperature today will be near 84?F (average is 73?F). Relative humidity: Below 50% by 11 a.m. and near 35% by 5 p.m. Surface winds: S-SW 5-10 mph this morning, becoming SW 5-10 mph this afternoon. Transport winds: S-SW 10-15 mph this morning, becoming W-SW 10-15 mph this afternoon. Mixing height: Rising to 3000 feet by 2 p.m. and reaching 5000 feet by 5 p.m. Salem's sunset tonight: 6:57 p.m. (Salem Airport data for Wednesday, September 27th: High 89?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: A storm system with breezy winds and scattered rain showers moves across the Willamette Valley on Friday, bringing wetting rains to the Silverton Hills. Isolated mountain thundershowers are possible in the late afternoon. Between 0.10-0.25 of an inch are expected by sunset Friday evening. Polar air pushes the jet stream over Oregon this weekend, with disturbances aloft creating frequent rain showers throughout the region. Temperatures will experience a dramatic drop below seasonal averages as a result, and widespread cloud cover will limit daytime heating. Unstable weather will persist into the first week of October, as the upper-level disturbance settles east of the Cascades. Moisture will continue to be drawn in from the Pacific Ocean, creating cloud cover with isolated rain showers. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 28 11:46:16 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 28 Sep 2017 18:46:16 +0000 Subject: [willamette-fcst] Field Burning Forecast - September 28, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT THU SEP 28, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The upper-level ridge has weakened and shifted east of the Cascades, turning flow aloft southerly overnight and SW later today as it enters Idaho. Gradients over the Coast Range and along the I-5 corridor have all turned positive, helping to push back the offshore flow between Salem & Redmond as southerly winds pick up. Mixing heights are rising steadily with warming and transport winds are turning more SW. A 1 p.m. PIBAL is scheduled, and if it confirms the positive trend, field burning may begin shortly afterwards. TODAY'S FORECAST: Increasing Clouds. Salem's high temperature today will be near 86?F (average is 73?F). Relative humidity: Below 50% now and nearing 25% by 5 p.m. Surface winds: S-SW 5-10 mph now, becoming SW 5-10 mph this afternoon. Transport winds: S-SW 10-15 mph now, becoming W-SW 10-15 mph this afternoon. Mixing height: Rising to 3000 feet by 2 p.m. and reaching 5000 feet by 5 p.m. Salem's sunset tonight: 6:57 p.m. (Salem Airport data for Wednesday, September 27th: High 89?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: A storm system with breezy winds and scattered rain showers moves across the Willamette Valley on Friday, bringing wetting rains to the Silverton Hills. Isolated mountain thundershowers are possible in the late afternoon. Between 0.10-0.25 of an inch are expected by sunset Friday evening. Polar air pushes the jet stream over Oregon this weekend, with disturbances aloft creating frequent rain showers throughout the region. Temperatures will experience a dramatic drop below seasonal averages as a result, and widespread cloud cover will limit daytime heating. Unstable weather will persist into the first week of October, as the upper-level disturbance settles east of the Cascades. Moisture will continue to be drawn in from the Pacific Ocean, creating cloud cover with isolated rain showers. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Tom Jenkins, AEM ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fbs.htm.doc Type: application/msword Size: 30208 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 29 08:44:27 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 29 Sep 2017 15:44:27 +0000 Subject: [willamette-fcst] Willamette Valley Field Burning Forecast Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT FRI SEP 29, 2017 ****This will be the last field burning forecast for the 2017 season.**** BURN ADVISORY: Recommended times for agricultural burning are from 9 a.m. until 5 p.m. Prep burning is not allowed. WEATHER DISCUSSION: A weakening cold front is pushing through the region this morning bringing light rain. Rain will turn to showers later this morning and afternoon with some partial afternoon clearing. Rainfall amounts will likely be about a tenth of an inch. Air mass destabilizes as cooler air moves in aloft from an upper level trough coming in behind the front. TODAY'S FORECAST: Cloudy with some light rain. Scattered showers this afternoon with partial clearing. Salem's high temperature near 67F (average is 72F). Relative humidity: Will lower to near 70 percent this afternoon. Surface winds: S this morning at 5 - 8 mph, becoming SW to W at 7 - 14 mph this afternoon. Transport winds: SSW this morning at 8 - 12 mph, becoming SW to W at 10 - 16 mph this afternoon. Mixing height: Near 2500 ft this morning, rising to 3000 - 3500 ft by noon, rising to 4000 - 4500 ft by 4 p.m. Salem's sunset tonight: 6:56 p.m. (Salem Airport data for Thursday, Sep. 28: High 86?F; Rainfall: .00") (Maximum Ventilation Index expected today: 63) EXTENDED DISCUSSION: Upper level trough moves over the state tomorrow with some colder air driving down from the north late Saturday and Sunday, helping to deepen the trough on Sunday. Expect cooler temperatures and scattered showers. Gradually, the trough moves eastward early next week with the air mass drying and a stabilizing. Wind flow turns from NW'erly on Saturday and Sunday to N to NE early next week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15 mph. 2. Transport winds are a layer average through the mixing height, weighted slightly toward the winds at the top of the layer. 3. Ventilation Index is the height of the mixing layer (ft) times the transport wind speed (mph) divided by 1000. 4. Surface wind direction is the general expected wind direction. At a specific point surface winds are highly dependent on local terrain conditions. 5. In accordance with OAR 837-110-0090, all field burning shall be banned when any two of the following criteria are present: A. Temperature of 95 degrees Fahrenheit or above B. Relative humidity of 30 percent or below C. Wind speed of 15 miles per hour or higher This forecast is provided under an agreement between the Oregon Department of Agriculture (ODA) and the Oregon Department of Forestry (ODF). For information contact ODA at 503-986-4701. To add/remove your email address from this list, please go to: http://listsmart.osl.state.or.us/mailman/listinfo/willamette-fcst Nick Yonker ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... 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