From willamette-fcst at listsmart.osl.state.or.us Tue Aug 1 08:52:21 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 1 Aug 2017 15:52:21 +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 TUE AUG 1, 2017 BURN ADVISORY: *** State Fire Marshal Burn-Ban Conditions are likely this afternoon. *** Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strengthening upper-level ridge has warmed the air aloft several degrees since Monday. That will support record-warm temperatures this afternoon, while keeping mixing suppressed. In addition, a building surface thermal trough, over northern California, will draw very dry and brisk northerly winds through the Willamette Valley, elevating the danger of wildfires. TODAY'S FORECAST: Sunny, hot, very dry, and breezy. Salem's high temperature today will be near 100?F (average is 84?F). Relative humidity: Dropping to 30% by noon and to near 17% by 5 p.m. Surface winds: NE 5-15 mph this morning; N 10-20 mph this afternoon. Transport winds: NE 15 mph this morning; N 20-25 mph this afternoon. Mixing height: Rising to 2000 feet by 11 a.m. and to 3000 feet by 5 p.m. Salem's sunset tonight: 8:38 p.m. (Salem Airport data for Monday, July 31st: High 95?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: The strength of the upper-level ridge should peak on Wednesday, with valley temperatures approaching all-time record highs. In addition, very dry N-NE winds will maintain high wildfire danger. Slight weakening of the upper-level ridge may shift the surface thermal trough east of the Cascades by late Thursday, but valley temperatures are likely to exceed 100?F for the third straight day. Dry and hot weather will continue on Friday. Increasing onshore flow should cool valley temperatures back into the upper 90s, but wildfire danger may remain too elevated to allow for burning. Gradual cooling will continue through the weekend but with a slight chance of thundershowers. 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. 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: 36352 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Aug 1 11:42:16 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 1 Aug 2017 18:42:16 +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 TUE AUG 1, 2017 BURN ADVISORY: *** State Fire Marshal Burn-Ban Conditions are likely this afternoon. *** Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level ridge has warmed the air aloft several degrees since Monday, which will suppress mixing and support record-warm temperatures today. In addition, very dry north winds will elevate wildfire danger. TODAY'S FORECAST: Sunny and hot. Salem's high temperature today will be near 100?F (the daily record of 100?F was set in 2015; the average is 84?F). Relative humidity: Near 30% at noon; dropping to near 17% by 5 p.m. Surface winds: N 8-18 mph. Transport winds: N 15-25 mph. Mixing height: Rising to 3000 feet by 5 p.m. Salem's sunset tonight: 8:38 p.m. (Salem Airport data for Monday, July 31st: High 95?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: The strength of the upper-level ridge should peak on Wednesday, with valley temperatures approaching all-time record highs. In addition, very dry N-NE winds will maintain high wildfire danger. On Thursday, valley temperatures are likely to exceed 100?F for the third straight day. Slight weakening of the upper-level ridge may shift the surface thermal trough east of the Cascades Thursday evening. Dry and hot weather will continue on Friday. Increasing onshore flow could cool valley temperatures back into the upper 90s, but wildfire danger may remain too elevated to allow for burning. A weak upper-level disturbance will introduce a slight chance of thundershowers over the weekend, while temperatures continue to slowly moderate. 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. 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: 36352 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Aug 2 08:42:41 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 2 Aug 2017 15:42:41 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 2, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT WED AUG 2, 2017 BURN ADVISORY: ***State Fire Marshal Burn-Ban conditions are expected this afternoon*** Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A compromised airshed and a challenging weather pattern make field burning operations appear unlikely for today. An upper-level ridge has shifted west of the Willamette River, creating N flow aloft that is pulling wildfire smoke down from Canada while negatively-stacked gradients draw smoke in from a much closer wildfire on Mt. Jefferson; air quality degradation will impact western Oregon until 7 p.m. Above-average temperatures, very low humidity, and strong N-NE surface winds this afternoon will meet State Fire Marshal Burn-Ban conditions. The gusty winds and intense heating will help mixing heights rise rapidly in the afternoon hours, improving air quality briefly until after sunset. TODAY'S FORECAST: Hazy with layers of smoke aloft. Salem's high temperature today will be near 105?F (average is 84?F). Relative humidity: Below 30% by 10:30 a.m. and nearing 14% by 5 p.m. Surface winds: N-NE 10-15 mph this morning and NE 10-15 mph this afternoon. Transport winds: NE 10-15 mph this morning and through the afternoon. Mixing height: Rising to 3000 feet around 12 p.m. and reaching 6,000 feet by 5 p.m. Salem's sunset tonight: 8:37 p.m. (Salem Airport data for Tuesday, August 1st: High 101?F; Rainfall: .00") (Maximum Ventilation Index expected today: 90) EXTENDED DISCUSSION: A blocking pattern is setting up ahead the weekend, with the upper-level ridge positioning itself over the Oregon coast. N-NW flow aloft will persist, as the ridge suppresses mixing and maintains poor air quality due to regional wildfire emissions. Temperatures will begin to lower as the heat wave breaks on Thursday evening, but remain above seasonal averages. Offshore flow will ease, but surface and transport winds will remain northerly, making conditions appear unfavorable for field burning for the remainder of the week. Weekend relief from afternoon temperatures above 100?F may not last, as the upper-level ridge begins to migrate back toward the Cascades 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Aug 2 11:45:07 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 2 Aug 2017 18:45:07 +0000 Subject: [willamette-fcst] Field Burn Forecast - August 2, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT WED AUG 2, 2017 BURN ADVISORY: ***State Fire Marshal Burn-Ban conditions are expected this afternoon*** Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A compromised airshed and a challenging weather pattern make field burning operations appear unlikely for today. An upper-level ridge has shifted west of the Willamette River, creating N flow aloft with offshore gradients pulling wildfire smoke through the Columbia River Gorge and across the Cascades from a wildfire near Mt. Jefferson. Degraded air quality will impact western Oregon until 7 p.m. Above-average temperatures, very low humidity, and strong N-NE surface winds this afternoon will meet State Fire Marshal Burn-Ban conditions. The gusty winds and intense heating will help mixing heights rise in the afternoon hours, improving air quality briefly until after sunset. TODAY'S FORECAST: Hazy with layers of smoke aloft. Salem's high temperature today will be near 105?F (average is 84?F). Relative humidity: Below 30% by 12:30 and nearing 14% by 5 p.m. Surface winds: N-NE 5-10 mph currently and NE 10-15 mph this afternoon. Transport winds: NE 10-15 mph currently and through the afternoon. Mixing height: Rising to 3000 feet around 1 p.m. and reaching 4,000 feet by 5 p.m. Salem's sunset tonight: 8:37 p.m. (Salem Airport data for Tuesday, August 1st: High 101?F; Rainfall: .00") (Maximum Ventilation Index expected today: 60) EXTENDED DISCUSSION: A blocking pattern is setting up ahead the weekend, with the upper-level ridge positioning itself over the Oregon coast. N-NW flow aloft will persist, as the ridge suppresses mixing and maintains poor air quality due to regional wildfire emissions. Temperatures will begin to lower as the heat wave breaks on Thursday evening, but remain above seasonal averages. Offshore flow will ease, but surface and transport winds will remain northerly, making conditions appear unfavorable for field burning for the remainder of the week. Weekend relief from afternoon temperatures above 100?F may not last, as the upper-level ridge begins to migrate back toward the Cascades 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Aug 3 08:38:12 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 3 Aug 2017 15:38:12 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 3, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT THU AUG 3, 2017 BURN ADVISORY: ***State Fire Marshal Burn-Ban conditions are expected this afternoon*** Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The upper-level ridge over the Oregon coast has weakened overnight, and flow aloft is becoming NW; as the atmosphere cools, it will trigger a slow end to our current heat wave. Offshore flow persists at the surface, with transport winds continuing to trap regional wildfire smoke throughout the Willamette Valley. State Fire Marshall Burn-Ban conditions will develop early this afternoon, with temperatures again peaking in the triple-digits. A mild sea breeze is expected to push in around sunset and improve air quality throughout the night, but a strong marine push is not expected. TODAY'S FORECAST: Hazy with layers of smoke aloft becoming Mostly Clear this evening. Salem's high temperature today will be near 106?F (average is 84?F). Relative humidity: Below 30% by 1 p.m. and nearing 17% by 5 p.m. Surface winds: Variable 5 mph or less this morning, becoming N 5-10 mph this afternoon and NW 10-15 mph this evening. Transport winds: N-NE 5-10 mph this morning, becoming N-NW 5-10 mph this afternoon and NW 15-20 mph this evening. Mixing height: Rising to 3000 feet around 3 p.m. and reaching 4,000 feet by 6 p.m. Salem's sunset tonight: 8:35 p.m. (Salem Airport data for Tuesday, August 1st: High 107?F; Rainfall: .00") (Maximum Ventilation Index expected today: 70) EXTENDED DISCUSSION: The upper-level ridge will continue to break down and retreat out to sea on Friday, turning flow aloft W-NW and allowing better mixing to occur with daytime heating. Onshore gradients may develop by mid-afternoon ahead of another mild sea breeze, but overall cooling may not be enough to reduce the threat of State Fire Marshal conditions. Saturday is expected to be the coolest day of the weekend, as a limited marine push brings morning clouds to the northern and southern ends of the Willamette Valley. Sunday, the upper-level ridge will begin to rebuild over western Oregon; this will cause gradients to flatten out and northerly flow to prevail across the Willamette Valley. Field burning opportunities will be determined by development of onshore gradients in the afternoon hours next week, but appear to trend positive as the week progresses and daily sea breezes further cool the atmosphere. 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. 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 -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Thu Aug 3 11:43:55 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 3 Aug 2017 18:43:55 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 3, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT THU AUG 3, 2017 BURN ADVISORY: ***State Fire Marshal Burn-Ban conditions are expected this afternoon*** Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The upper-level ridge over the Oregon coast has weakened overnight, and flow aloft is becoming N-NW; as the atmosphere cools, it will trigger a slow end to our current heat wave. Offshore flow persists at the surface, with transport winds continuing to trap regional wildfire smoke throughout the Willamette Valley. State Fire Marshall Burn-Ban conditions will develop early this afternoon, with temperatures again peaking in the triple-digits. A mild sea breeze is expected to push in around sunset and improve air quality throughout the night, but a strong marine push is not expected. TODAY'S FORECAST: Hazy with layers of smoke aloft becoming Mostly Clear this evening. Salem's high temperature today will be near 106?F (average is 84?F). Relative humidity: Below 30% by 1 p.m. and nearing 17% by 5 p.m. Surface winds: N-NE 5-10 mph this afternoon and N-NW 10-15 mph this evening. Transport winds: N-NW 5-10 mph this afternoon and NW 15-20 mph this evening. Mixing height: Rising to 3000 feet around 3 p.m. and reaching 4,000 feet by 6 p.m. Salem's sunset tonight: 8:35 p.m. (Salem Airport data for Tuesday, August 1st: High 107?F; Rainfall: .00") (Maximum Ventilation Index expected today: 70) EXTENDED DISCUSSION: The upper-level ridge will continue to break down and retreat out to sea on Friday, turning flow aloft W-NW and allowing better mixing to occur with daytime heating. Onshore gradients may develop by mid-afternoon ahead of another mild sea breeze, but overall cooling may not be enough to reduce the threat of State Fire Marshal conditions. Saturday is expected to be the coolest day of the weekend, as a limited marine push brings morning clouds to the northern and southern ends of the Willamette Valley. Sunday, the upper-level ridge will begin to rebuild over western Oregon; this will cause gradients to flatten out and northerly flow to prevail across the Willamette Valley. Field burning opportunities will be determined by development of onshore gradients in the afternoon hours next week, but appear to trend positive as the week progresses and daily sea breezes further cool the atmosphere. 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Aug 4 08:56:10 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 4 Aug 2017 15:56:10 +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 AUG 4, 2017 BURN ADVISORY: *** State Fire Marshal Burn-Ban Conditions possible this afternoon. *** Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The strong upper-level ridge that has been responsible for the record-breaking heat this week has shifting into the eastern Gulf of Alaska. A dry upper-level trough is dropping into the northern Rockies and has induced onshore flow, at all levels, across western Oregon. That will cool temperatures about 8-10 degrees today and begin to push the wildfire smoke out of the valley. The air aloft is still quite warm, so mixing heights will be slow to rise this afternoon. State Fire Marshal Burn Ban Conditions may be reached late this afternoon, due to warm temperatures and low humidity. TODAY'S FORECAST: Sunny and smoky. Not as hot. Gradually improving air quality. Salem's high temperature today will be near 95?F (average is 84?F). Relative humidity: Dropping to 40% by noon and to near 25% by 5 p.m. Surface winds: SW 5-10 mph; becoming W 5-10 mph late afternoon. Transport winds: SW 10 mph this morning; W 10-15 mph this afternoon. Mixing height: Rising to 3000 about 3 p.m. and to 4000 feet by 5 p.m. Salem's sunset tonight: 8:34 p.m. (Salem Airport data for Thursday, August 3rd: High 103?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: The upper-level ridge is expected to move back over Oregon this weekend through at least early next week. However, it is not expected to be as strong as it was earlier this week. Onshore flow will be weak but should hold high temperatures below the century mark and help to keep additional wildfire smoke for entering the airshed. A weak upper-level disturbance is expected to undercut the ridge and bring a chance of thunderstorms to southern Oregon beginning late this weekend. Storms are not expected to make it as far north as the Willamette Valley, but that can't be ruled out. Some long-range computer models show the upper-level ridge weakening and progressing east of the region later 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. 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 Fri Aug 4 11:40:14 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 4 Aug 2017 18:40:14 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:40 AM PDT FRI AUG 4, 2017 BURN ADVISORY: *** State Fire Marshal Burn-Ban Conditions possible this afternoon. *** Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Nephelometer readings indicate that significant wildfire smoke remains across the Willamette Valley. A dry upper-level trough is dropping into the northern Rockies and has induced onshore flow, at all levels, across western Oregon. That will cool temperatures about 6-10 degrees today and begin to improve air quality. Warm air aloft will continue to inhibit mixing. TODAY'S FORECAST: Sunny and smoky. Not as hot. Gradually improving air quality. Salem's high temperature today will be near 95?F (average is 84?F). Relative humidity: Dropping to near 25% by 5 p.m. Surface winds: SW 5-10 mph; becoming W 5-10 mph late afternoon. Transport winds: SW 10 mph; becoming W 10-15 mph late this afternoon. Mixing height: Rising to 3000 about 3 p.m. and to 4000 feet by 5 p.m. Salem's sunset tonight: 8:34 p.m. (Salem Airport data for Thursday, August 3rd: High 103?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: An upper-level ridge is expected to move back over Oregon this weekend through at least early next week. However, it is not expected to be as strong as it was earlier this week. Onshore flow will be weak but should hold high temperatures below the century mark and help to keep additional wildfire smoke for entering the airshed. A weak upper-level disturbance is expected to undercut the ridge and bring a chance of thunderstorms to southern Oregon beginning Sunday. Storms are not expected to make it as far north as the Willamette Valley, but that can't be ruled out. Some long-range computer models show the upper-level ridge weakening and progressing east of the region later 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. 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: 36352 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Aug 7 08:42:20 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 7 Aug 2017 15:42:20 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 7, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT MON AUG 7, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Mediocre mixing this afternoon with questionable gradients create a challenging environment for field burning today. An upper-level ridge moves over the Oregon coast today, and will begin to warm the atmosphere as mixing becomes restricted. Mixing heights will struggle to reach 3,000ft briefly this afternoon, while transport winds become N-NW by early afternoon. Temperatures, wind speeds, and humidity do not appear to reach State Fire Marshal conditions today. Cloud cover across the Cascades and central Oregon may prevent onshore gradients from positively stacking this afternoon. TODAY'S FORECAST: Mostly Cloudy with Smoke & Haze. Salem's high temperature today will be near 92?F (average is 84?F). Relative humidity: Below 60% by 11 a.m. and nearing 35% by 5 p.m. Surface winds: Variable 5 mph or less this morning, becoming N 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 5 p.m. Salem's sunset tonight: 8:30 p.m. (Salem Airport data for Sunday, August 6th: High 91?F; Rainfall: .00") (Maximum Ventilation Index expected today: 30) EXTENDED DISCUSSION: Conditions for the week ahead do not favor safe, effective field burning opportunities. The upper-level ridge will slowly strengthen over NW Oregon through mid-week, further limiting mixing conditions as the flow aloft turns more N-NE by Tuesday afternoon. This shift to offshore flow will cause temperatures to climb higher as another heat wave develops, and the offshore flow will also draw more regional wildfire smoke into the Willamette Valley from across the Cascades. There will be little change for Wednesday and Thursday, as the heat wave reaches its apex and the reduced humidity appear likely to meet State Fire Marshal conditions each day. The suppressed mixing during daytime heating will also make air quality progressively worse as the week continues, with regional wildfire smoke being funneled through the Columbia River Gorge and Santiam Pass. 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Aug 7 11:48:45 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 7 Aug 2017 18:48:45 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 7, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT MON AUG 7, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Mediocre mixing this afternoon with questionable gradients create a challenging environment for field burning today. An upper-level ridge moves over the Oregon coast today, and will begin to warm the atmosphere as mixing becomes restricted. Mixing heights will struggle to reach 3,000ft briefly this afternoon, while transport winds become N-NW by early afternoon. Temperatures, wind speeds, and humidity do not appear to reach State Fire Marshal conditions today. Cloud cover across the Cascades and central Oregon may prevent onshore gradients from positively stacking this afternoon. TODAY'S FORECAST: Partly Cloudy with Smoke & Haze. Salem's high temperature today will be near 92?F (average is 84?F). Relative humidity: Below 60% currently and nearing 35% by 5 p.m. Surface winds: Variable 5 mph or less this morning, becoming N 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 5 p.m. Salem's sunset tonight: 8:30 p.m. (Salem Airport data for Sunday, August 6th: High 91?F; Rainfall: .00") (Maximum Ventilation Index expected today: 30) EXTENDED DISCUSSION: Conditions for the week ahead do not favor effective field burning opportunities. The upper-level ridge will slowly strengthen over NW Oregon through mid-week, further limiting mixing conditions as the flow aloft turns more N-NE by Tuesday afternoon. This shift to offshore flow will cause temperatures to climb higher and the offshore flow will also draw more regional wildfire smoke into the Willamette Valley from across the Cascades. There will be little change for Wednesday and Thursday, as heating continues to increase and the reduced humidity appear likely to meet State Fire Marshal conditions each day. The suppressed mixing during daytime heating will also make air quality progressively worse as the week continues, with regional wildfire smoke being funneled through the Columbia River Gorge and Santiam Pass. 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Aug 8 08:45:29 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 8 Aug 2017 15:45:29 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 8, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT TUE AUG 8, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Very similar conditions to Monday, but slightly warmer under clear skies. The upper-level ridge has anchored in place near the NW Oregon coast, and will limit mixing today as offshore flow develops. Remnant smoke from regional wildfires and afternoon haze will be the only factors to limit heating, allowing late afternoon temperatures to approach 95?F; humidity will be closely monitored for potential State Fire Marshal conditions later today. TODAY'S FORECAST: Mostly Clear with Smoke & Haze. Salem's high temperature today will be near 95?F (average is 84?F). Relative humidity: Below 60% by 10:30 a.m. and nearing 30% by 5 p.m. Surface winds: Variable 5 mph or less this morning, becoming N 5-10 mph this afternoon. Transport winds: N 5-10 mph this morning, becoming N-NE 5-10 mph this afternoon. Mixing height: Rising to 3000 feet by 5 p.m. Salem's sunset tonight: 8:28 p.m. (Salem Airport data for Monday, August 7th: High 93?F; Rainfall: .00") (Maximum Ventilation Index expected today: 30) EXTENDED DISCUSSION: Little change in the weather pattern for the remainder of the week. The upper-level ridge will slowly strengthen over NW Oregon, further limiting mixing conditions as the atmosphere continues to warm & dry out. The offshore flow increases and will also draw more regional wildfire smoke into the Willamette Valley from across the Cascades. Poor mixing and degraded air quality will persist, along with the above-average temperatures for early August, through Friday, when the upper-level ridge begins to weaken and shift east towards the Cascades. Onshore flow will redevelop this weekend as a disturbance over the Pacific approaches, bringing cooler air and more favorable conditions for field burning mid-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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Aug 8 11:40:09 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 8 Aug 2017 18:40:09 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 8, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT TUE AUG 8, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Very similar conditions to Monday, but slightly warmer under clear skies. The upper-level ridge has anchored in place near the NW Oregon coast, and will limit mixing today as offshore flow develops. Mixing heights, mid-valley gradients, and transport winds all appear unlikely to support field burning today. Remnant smoke from regional wildfires and afternoon haze will be the only factors to limit heating, allowing late afternoon temperatures to approach 95?F; humidity remains elevated, making State Fire Marshal conditions unlikely. TODAY'S FORECAST: Mostly Clear with Smoke & Haze. Salem's high temperature today will be near 95?F (average is 84?F). Relative humidity: Reaching 35% by 5 p.m. Surface winds: Variable 5 mph or less currently, becoming N 5-10 mph this afternoon. Transport winds: N 5-10 mph currently, becoming N-NE 5-10 mph this afternoon. Mixing height: Rising to 3000 feet by 5 p.m. Salem's sunset tonight: 8:28 p.m. (Salem Airport data for Monday, August 7th: High 93?F; Rainfall: .00") (Maximum Ventilation Index expected today: 30) EXTENDED DISCUSSION: Little change in the weather pattern for the remainder of the week. The upper-level ridge will slowly strengthen over NW Oregon, further limiting mixing conditions as the atmosphere continues to warm & dry out. The offshore flow increases and will also draw more regional wildfire smoke into the Willamette Valley from across the Cascades. Poor mixing and degraded air quality will persist, along with the above-average temperatures for early August, through Friday, when the upper-level ridge begins to weaken and shift east towards the Cascades. Onshore flow will redevelop this weekend as a disturbance over the Pacific approaches, bringing cooler air and a chance of wetting rains to the Silverton Hills on Monday 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Aug 9 08:50:35 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 9 Aug 2017 15:50:35 +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 AUG 9, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: There has been little change in the overall weather pattern since Tuesday. A strong upper-level ridge remains anchored over southern British Columbia and will provide another day of sunshine with well-above-average temperatures. Nephelometer readings remain elevated, due to wildfire smoke. Limited mixing and light winds will not provide much improvement in air quality today. Meanwhile, a weak upper-level trough, just off the northern California coast, will bring scattered thundershowers to southern Oregon again this afternoon. Storms could make is as far north as the central Oregon Cascades. TODAY'S FORECAST: Sunny and warm. Continued smoky. Salem's high temperature today will be near 95?F (average is 83?F). Relative humidity: Dropping to 50% by 11 a.m. and to near 30% by 5 p.m. Surface winds: Light; becoming N 5-10 mph this afternoon. Transport winds: Light; becoming N 5-10 mph this afternoon. Mixing height: Rising to 2000 by noon and to 3500 feet by 5 p.m. Salem's sunset tonight: 8:27 p.m. (Salem Airport data for Tuesday, August 8th: High 95?F; Rainfall: .00") (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: Thursday will be similar to today, except thundershowers may migrate a little farther north. There is a risk of storms making it as far north and west as the Willamette Valley Thursday evening through early Friday. The upper-level ridge will progress east of the state on Friday with SW flow aloft bringing more stable conditions to western Oregon. Increasing onshore flow should improve air quality and initiate a cooling trend. Temperatures will cool back to seasonal averages over the weekend, but the threat of precipitation looks minimal. 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. 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: 36352 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Aug 9 11:54:13 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 9 Aug 2017 18:54:13 +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 AUG 9, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The weather pattern is virtually identical to yesterday, and valley temperatures are essentially the same as they were 24 hours ago. Wildfire smoke continues to keep nephelomter readings significantly elevated. Poor mixing and light winds will provide little improvement in air quality today. Meanwhile, a weak upper-level trough, just off the northern California coast, will bring scattered thundershowers to southern Oregon again this afternoon. Storms could make is as far north as the central Oregon Cascades. TODAY'S FORECAST: Sunny and warm. Continued smoky. Salem's high temperature today will be near 95?F (average is 83?F). Relative humidity: Dropping to near 30% by 5 p.m. Surface winds: Light; becoming N 5-10 mph. Transport winds: Light; becoming N 5-10 mph. Mixing height: Rising to just 3500 feet by 5 p.m. Salem's sunset tonight: 8:27 p.m. (Salem Airport data for Tuesday, August 8th: High 95?F; Rainfall: .00") (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: Thundershowers will migrate farther north Thursday afternoon and evening. Storms could make it as far north as the Willamette Valley late Thursday through Friday. Local rainfall totals near .10" are possible. Increasing onshore flow should improve air quality and progressively cool temperatures Friday and Saturday. Strengthening onshore flow may produce morning drizzle on Sunday, as temperatures drop back to slightly-below average. A dry onshore flow pattern may bring favorable 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. 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: 36352 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Aug 10 08:54:23 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 10 Aug 2017 15:54:23 +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 AUG 10, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level ridge, centered over southern British Columbia, is being undercut by a moist and unstable upper-level trough moving into northern California. With the exception of the immediate coastline, northern Oregon has stayed sunny and hot, with highly-elevated nephelometer readings due to wildfire smoke. In addition to the wildfire smoke, southern Oregon has also been getting significant thundershower activity all week. Today will be another sunny, hot, and smoky day for NW Oregon. However, moisture and instability from the California system will push further northward, inducing thundershower development over the central and possibly northern Cascades. There is also a risk of thundershowers moving off the Cascades and over the Willamette Valley late today and tonight. These would be slow-moving storms with potentially wetting rains. TODAY'S FORECAST: Sunny and warm. Continued smoky. Chance of thundershowers late. Salem's high temperature today will be near 95?F (average is 83?F). Relative humidity: Dropping to 50% by noon and to near 30% by 5 p.m. Surface winds: Light; becoming N 5-10 mph this afternoon. Transport winds: NE 5 mph; becoming N 10 mph this afternoon. Mixing height: Rising to 2000 by noon and to 3000 feet by 5 p.m. Salem's sunset tonight: 8:25 p.m. (Salem Airport data for Wednesday, August 9th: High 96?F; Rainfall: .00") (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: Southerly flow aloft will keep skies at least partly cloudy on Friday, and the threat of thundershowers can't be ruled out. Storms could produce rainfall in excess of .10". Increasing onshore flow will begin a cooling trend and may bring some morning marine clouds into the valley. An approaching upper-level trough will turn the flow aloft southwesterly over the weekend, which should further increase the onshore flow and stabilize the air mass. Although the threat of thunderstorms will decrease, a weak cold front may bring drizzle or a few light showers on Sunday. Rainfall amounts should be generally less than .10". Temperatures should cool into the 80s Friday and Saturday and the 70s on Sunday. A generally dry and stable onshore flow pattern may bring favorable 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. 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 Thu Aug 10 11:55:40 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 10 Aug 2017 18:55:40 +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 AUG 10, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong upper-level ridge will bring another sunny and warm afternoon to NW Oregon, but along with considerable wildfire smoke. A weather system over northern California will push enough moisture and instability northward for thundershower development over the Cascades this afternoon. Light SE winds aloft could push some storms over the Willamette Valley, from this evening through tonight, mainly south of Salem. TODAY'S FORECAST: Sunny and warm. Continued smoky. Risk of a thundershower late. Salem's high temperature today will be near 95?F (average is 83?F). Relative humidity: Dropping to 30% by 5 p.m. Surface winds: Light; becoming N 5-10 mph. Transport winds: NE 5 mph; becoming N 10 mph. Mixing height: Rising to 3000 feet by 5 p.m. Salem's sunset tonight: 8:25 p.m. (Salem Airport data for Wednesday, August 9th: High 96?F; Rainfall: .00") (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: Southerly flow aloft will keep skies at least partly cloudy on Friday, and maintain a threat of a thundershower. Increasing onshore flow will begin a cooling trend and may bring some morning marine clouds into the valley. Increasing SW flow aloft, and onshore flow at the surface, will cool and stabilize the air mass this weekend. The threat of thunderstorms will decrease, but a weak cold front may bring drizzle or light showers on Sunday. Rainfall amounts should be less than .10". Temperatures will cool from the mid-80s on Saturday to the mid-70s on Sunday. A generally dry and stable onshore flow pattern may bring favorable 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. 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: 36352 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Aug 11 08:54:48 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 11 Aug 2017 15:54:48 +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 AUG 11, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: Thundershowers developed over the Cascades Thursday afternoon, and SE flow aloft pushed them over portions of the Willamette Valley Thursday night. The storms weakened as they moved over the valley, so rainfall was spotty and light. The shower activity has ended, but residual clouds remain over the region this morning. Air quality has improved, but nephelometer readings remain modestly elevated due to wildfire smoke. The strong upper-level ridge that has been anchored over southern British Columbia this week is finally shifting eastward, in response to an approaching trough from the Gulf of Alaska. SE winds aloft this morning should turn more southerly later today, so thundershower activity will be less likely to migrate over the Willamette Valley from the Cascades. Although the air aloft will be cooling today, it is still quite warm, so mixing heights will be slow to rise and will likely stay below 4000 feet. The surface thermal trough has finally pushed into central Oregon. Onshore flow will slowly increase today, which should continue to clear the wildfire smoke from western Oregon. TODAY'S FORECAST: Partly cloudy and cooler. Afternoon thunderstorms likely over the Cascades. Salem's high temperature today will be near 86?F (average is 83?F). Relative humidity: Dropping to 60% by 11 a.m. and to near 40% by 5 p.m. Surface winds: SW 5 mph; becoming WNW 5-10 mph by late this afternoon. Transport winds: SW 5 mph; becoming WNW 5-10 mph by late this afternoon...shearing to southerly at the mixing height. Mixing height: Rising to about 2000 by noon and to near 3500 feet by 5 p.m. Salem's sunset tonight: 8:24 p.m. (Salem Airport data for Thursday, August 10th: High 92?F; Rainfall: .00") (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: Increasing SW flow aloft, and onshore flow at the surface, will cool and stabilize the air mass this weekend. The threat of thunderstorms will end, but a weak cold front will likely bring some light rain to NW Oregon on Sunday...mainly from Salem north. Rainfall amounts should be around .10" or less in the Silverton Hills. Temperatures will cool from the low-80s on Saturday to the mid-70s on Sunday. A generally dry and stable onshore flow pattern next week will allow temperatures to slowly warm back to seasonal averages with possible 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. 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 Fri Aug 11 11:51:16 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 11 Aug 2017 18:51:16 +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 AUG 11, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The strong upper-level ridge that has been anchored over southern British Columbia this week is finally shifting eastward, in response to an approaching trough from the Gulf of Alaska. SE winds aloft should turn more southerly later today, which will likely keep afternoon thundershower development over the Cascades. Although the air aloft will be cooling today, it is still quite warm, so mixing heights will be slow to rise, likely staying below 4000 feet. The surface thermal trough has finally pushed into central Oregon. Onshore flow will slowly increase today, which should continue to clear the wildfire smoke from the area. TODAY'S FORECAST: Partly cloudy and cooler. Scattered thunderstorms developing over the Cascades later this afternoon. Salem's high temperature today will be near 86?F (average is 83?F). Relative humidity: Dropping to near 40% by 5 p.m. Surface winds: SW 5 mph; becoming WNW 5-10 mph by late this afternoon. Transport winds: SW 5 mph; becoming WNW 5-10 mph by late this afternoon...shearing to southerly at the mixing height. Mixing height: Rising to about 3500 feet by 5 p.m. Salem's sunset tonight: 8:24 p.m. (Salem Airport data for Thursday, August 10th: High 92?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 35) EXTENDED DISCUSSION: Increasing SW flow aloft, and onshore flow at the surface, will cool and stabilize the air mass this weekend. The threat of thunderstorms will end, but a weak cold front will likely bring some light rain to NW Oregon on Sunday...mainly from Salem north. The latest computer guidance gives Salem about one-tenth of an inch of rain, which would be the first measurable rain since June 16th. Temperatures will cool from the low-80s on Saturday to the mid-70s on Sunday. A generally dry and stable onshore flow pattern next week will allow temperatures to slowly warm back to seasonal averages with possible 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. 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: 36864 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Aug 14 08:40:07 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 14 Aug 2017 15:40:07 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 14, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT MON AUG 14, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed between 11 a.m. and 2 p.m. with a 50 acre limit. WEATHER DISCUSSION: Northwesterly flow aloft will continue to cool the atmosphere and promote mixing with daytime heating, while onshore surface flow pushes into Oregon. Air quality throughout the valley has improved substantially over the past few days. The Columbia River gradients are slightly stronger than mid-valley, keeping transport winds northerly until this afternoon. Consequently, gradients will be the limiting factor for field burning today, and will be monitored carefully. TODAY'S FORECAST: Mostly Cloudy becoming Partly Cloudy this afternoon. Salem's high temperature today will be near 77?F (average is 83?F). Relative humidity: Below 60% by 11 a.m. and nearing 40% by 5 p.m. Surface winds: N 5-10 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 11 a.m. and reaching 4000 feet by 2 p.m. Salem's sunset tonight: 8:19 p.m. (Salem Airport data for Sunday, August 13th: High 76?F; Rainfall: .06") (Maximum Ventilation Index expected today: 40) EXTENDED DISCUSSION: Tuesday appears to develop more favorable field burning opportunities than Monday, thanks to an upper-level disturbance that will drive down the Willamette Valley, creating westerly flow aloft. Onshore flow at the surface will continue to build, and mixing heights should rise higher with daytime heating. No rainfall is expected to fall over the Silverton Hills. Wednesday and Thursday will see an upper-level ridge begin to reform over the Pacific Ocean, turning flow aloft more NW through midweek. Onshore surface and transport winds will continue to develop, possibly enhancing field burning opportunities Wednesday afternoon ahead of a deep marine push. Morning clouds are expected to linger over the Willamette Valley, making it difficult to heat the atmosphere and create atmospheric mixing on Thursday. Friday's weather appears to be sunnier with temperatures rising back near seasonal averages, and may allow a strong finish ahead of the weekend for 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Aug 14 11:48:47 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 14 Aug 2017 18:48:47 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 14, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT MON AUG 14, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed between 11 a.m. and 2 p.m. with a 50 acre limit. WEATHER DISCUSSION: Northwesterly flow aloft will continue to cool the atmosphere and promote mixing with daytime heating, while onshore surface flow pushes into Oregon. Gradients remain onshore, with mid-valley flow continuing to slowly develop, so the 1 p.m. PIBAL will help indicate when this process speeds up under afternoon sunshine. This may push the window for potential field burning back until an early evening sea breeze helps produce W-NW transport winds. TODAY'S FORECAST: Mostly Cloudy becoming Partly Cloudy this afternoon. Salem's high temperature today will be near 77?F (average is 83?F). Relative humidity: Below 60% currently and nearing 40% by 5 p.m. Surface winds: N-NW 5-10 mph this afternoon and W-NW 8-12 mph this evening. Transport winds: N-NW 5-10 mph this afternoon and NW 10-15 mph this evening. Mixing height: Rising to 3000 feet by 11 a.m. and reaching 4000 feet by 2 p.m. Salem's sunset tonight: 8:19 p.m. (Salem Airport data for Sunday, August 13th: High 76?F; Rainfall: .06") (Maximum Ventilation Index expected today: 40) EXTENDED DISCUSSION: Tuesday appears to develop more favorable field burning opportunities than Monday, thanks to an upper-level disturbance that will drive down the Willamette Valley, creating westerly flow aloft. Onshore flow at the surface will continue to build, and mixing heights should rise higher with daytime heating. No rainfall is expected to fall over the Silverton Hills. Wednesday and Thursday will see an upper-level ridge begin to reform over the Pacific Ocean, turning flow aloft more NW through midweek. Onshore surface and transport winds will continue to develop, possibly enhancing field burning opportunities Wednesday afternoon ahead of a deep marine push. Morning clouds are expected to linger over the Willamette Valley, making it difficult to heat the atmosphere and create atmospheric mixing on Thursday. Friday's weather appears to be sunnier with temperatures rising back near seasonal averages, and may allow a strong finish ahead of the weekend for 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Aug 15 08:45:32 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 15 Aug 2017 15:45:32 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 15, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT TUE AUG 15, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: W-NW flow aloft increases today, as an upper-level disturbance dives across SW Oregon. This feature will provide a mid-afternoon boost to onshore surface gradients as the sea breeze enters the Willamette Valley, signaling a later start time for potential field burning today. NW surface and transport winds will persist into the evening hours tonight. TODAY'S FORECAST: Partly Cloudy. Salem's high temperature today will be near 80?F (average is 83?F). Relative humidity: Below 60% by 11 a.m. and nearing 35% by 5 p.m. Surface winds: N 5 mph this morning, becoming NW 5-10 mph this afternoon. Transport winds: N 5-10 mph this morning, becoming NW 5-10 mph this afternoon. Mixing height: Rising to 3000 feet by 1 p.m. and reaching 4000 feet by 3 p.m. Salem's sunset tonight: 8:18 p.m. (Salem Airport data for Monday, August 14th: High 75?F; Rainfall: .00") (Maximum Ventilation Index expected today: 40) EXTENDED DISCUSSION: NW flow aloft develops as an upper-level ridge continues to build over Oregon on Wednesday. Onshore surface gradients appear to stack positively by mid-afternoon, bringing in a strong sea breeze ahead of a marine push Wednesday evening. With appropriate timing, this could be an optimal day for field burning operations. Thursday will see the upper-level ridge move over western Oregon, turning flow aloft light. Widespread cloud cover in the valley will delay heating, and the mixing needed for good smoke ventilation will be suppressed further by the ridge overhead. The weather pattern transitions back to a more favorable set-up Thursday evening, as the upper-level ridge flattens and opens W flow aloft. This will cool the atmosphere further, and allow stronger onshore gradients to develop, possibly by noon on Friday. This scenario, if it bears out, could present a full day of field burning opportunities ahead of the Eclipse 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Aug 15 11:46:28 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 15 Aug 2017 18:46:28 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 15, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT TUE AUG 15, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: W-NW flow aloft increases today, as an upper-level disturbance dives across SW Oregon. Mid-valley gradients appear to be developing faster than Columbia River gradients, and mixing heights are rising as expected. The sea breeze will come into the valley this afternoon and turn surface & transport flow NW, persisting into the early evening hours. TODAY'S FORECAST: Partly Cloudy. Salem's high temperature today will be near 80?F (average is 83?F). Relative humidity: Below 60% now and nearing 35% by 5 p.m. Surface winds: N 5 mph currently, becoming NW 5-10 mph this afternoon. Transport winds: N-NW 5-10 mph currently, becoming NW 5-10 mph this afternoon. Mixing height: 3000 feet currently and reaching 4500 feet by 4 p.m. Salem's sunset tonight: 8:18 p.m. (Salem Airport data for Monday, August 14th: High 75?F; Rainfall: .00") (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: NW flow aloft develops as an upper-level ridge continues to build over Oregon on Wednesday. Onshore surface gradients appear to stack positively by mid-afternoon, bringing in a strong sea breeze ahead of a marine push Wednesday evening. With appropriate timing, this could be an optimal day for field burning operations. Thursday will see the upper-level ridge move over western Oregon, turning flow aloft light. Widespread cloud cover in the valley will delay heating, and the mixing needed for good smoke ventilation will be suppressed further by the ridge overhead. The weather pattern transitions back to a more favorable set-up Thursday evening, as the upper-level ridge flattens and opens W flow aloft. This will cool the atmosphere further, and allow stronger onshore gradients to develop, possibly by noon on Friday. This scenario, if it bears out, could present a full day of field burning opportunities ahead of the Eclipse 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. 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: 29184 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Aug 16 08:55:58 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 16 Aug 2017 15:55:58 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 16, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:50 AM PDT WED AUG 16, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed between 12 p.m. and 2 p.m. with a 50 acre limit. WEATHER DISCUSSION: A weak upper-level ridge approaches Oregon today, turning flow NW aloft as it arrives. Surface onshore gradients will steadily build and should be positively stacked by mid-afternoon. Surface wind direction will remain the limiting factor, as transport winds will turn NW early this afternoon. A deep marine push will enter the valley by sunset, and bring extensive cloud cover overnight. TODAY'S FORECAST: Mostly Clear with Increasing Clouds late this afternoon. Salem's high temperature today will be near 86?F (average is 83?F). Relative humidity: Below 60% by 9 a.m. and nearing 35% by 5 p.m. Surface winds: N 5-10 mph this morning, becoming NW 5-10 mph after 3 p.m. Transport winds: N 5-10 mph this morning, becoming NW 5-10 mph after 1 p.m. Mixing height: Rising to 3000 feet by 12 p.m. and reaching 5000 feet by 3 p.m. Salem's sunset tonight: 8:16 p.m. (Salem Airport data for Tuesday, August 15th: High 83?F; Rainfall: .00") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: The upper-level ridge will loiter over western Oregon on Thursday, turning flow aloft light as mixing is suppressed. Clouds in the valley will be slow to break up, keeping temperatures mild for the entire day. The upper-level ridge will begin to weaken and flatten out as Thursday night progresses, allowing W flow aloft to begin cooling the atmosphere again. Onshore surface gradients may develop early on Friday morning, and mixing heights will no longer be limited as sunshine falls upon the Willamette Valley, indicating potential field burning opportunities ahead of the weekend. Weather appears mild for the Eclipse Weekend, as a weak upper-level disturbance pushes across the Willamette Valley and stalls out along the California coast early next week. This passing feature will generate some clouds to provide cooling shade to the Silverton Hills, but no rainfall is expected. Fair weather should persist through Monday for the Oregon Eclipse, but models indicate a potential turn to offshore flow with temperatures returning above seasonal averages next week after the Sun reappears; this scenario will be evaluated further as it could pull regional wildfire smoke across the Cascades 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: 30720 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Aug 16 11:43:18 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 16 Aug 2017 18:43:18 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 16, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT WED AUG 16, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed between 12 p.m. and 2 p.m. with a 50 acre limit. WEATHER DISCUSSION: A weak upper-level ridge approaches Oregon today, turning flow NW aloft as it arrives. Onshore gradients are slowly increasing, but this trend will speed up as the afternoon progresses. Transport winds are beginning to turn NW throughout the valley, but surface wind direction remains the primary limiting factor at this time to begin field burning. TODAY'S FORECAST: Mostly Clear with Increasing Clouds late this afternoon. Salem's high temperature today will be near 86?F (average is 83?F). Relative humidity: Below 40% currently and nearing 30% by 5 p.m. Surface winds: N 5-10 mph currently, becoming NW 5-10 mph after 3 p.m. Transport winds: N-NW 5-10 mph currently, becoming NW 5-10 mph after 1 p.m. Mixing height: 3000 feet currently, rising to 5000 feet by 3 p.m. Salem's sunset tonight: 8:16 p.m. (Salem Airport data for Tuesday, August 15th: High 83?F; Rainfall: .00") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: The upper-level ridge will loiter over western Oregon on Thursday, turning flow aloft light as mixing is suppressed. Clouds in the valley will be slow to break up, keeping temperatures mild for the entire day. The upper-level ridge will begin to weaken and flatten out as Thursday night progresses, allowing W flow aloft to begin cooling the atmosphere again. Onshore surface gradients may develop early on Friday morning, and mixing heights will no longer be limited as sunshine falls upon the Willamette Valley, indicating potential field burning opportunities ahead of the weekend. Weather appears mild for the Eclipse Weekend, as a weak upper-level disturbance pushes across the Willamette Valley and stalls out along the California coast early next week. This passing feature will generate some clouds to provide cooling shade to the Silverton Hills, but no rainfall is expected. Fair weather should persist through Monday for the Oregon Eclipse, with seasonable temperatures through the 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 Thu Aug 17 08:58:25 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 17 Aug 2017 15:58:25 +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 AUG 17, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from noon until 2 p.m. with a 50 acre limit. WEATHER DISCUSSION: Onshore flow brought a fresh surge of marine air into NW Oregon overnight with low clouds blanketing most of the Willamette Valley this morning. A strengthening upper-level ridge will warm the air aloft and clear the marine clouds from the valley this afternoon. Negatively-stacked onshore pressure gradients will struggle to balance-out this afternoon. Transport winds will back from NE to N this afternoon and possibly to the NNW late. TODAY'S FORECAST: Cloudy this morning; becoming sunny and warm this afternoon. Salem's high temperature today will be near 85?F (average is 82?F). Relative humidity: Dropping to 60% by noon and to near 30% by 5 p.m. Surface winds: N 5-10 mph. Transport winds: NNE 10 mph this morning; N 10 mph this afternoon. Mixing height: Rising to 3000 by noon and to near 4500 feet by 5 p.m. Salem's sunset tonight: 8:14 p.m. (Salem Airport data for Wednesday, August 16th: High 87?F; Rainfall: .00") (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: Friday should be mostly sunny with seasonal temperatures. A weak weather system will flatten the upper-level ridge and slightly increase the onshore flow late in the day. Expect morning marine clouds with sunny afternoons and seasonal temperatures this weekend. By Monday, the upper-level ridge will rebuild over the region, with only patchy morning clouds along the immediate coastline. Valley temperatures should climb back into the upper 80s. The upper-level ridge will progress eastward by mid-week. Increasing SW flow aloft will initiate a cooling trend and may create favorable burning 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. 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: 36352 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Aug 17 09:56:43 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 17 Aug 2017 16:56:43 +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 AUG 17, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from noon until 2 p.m. with a 50 acre limit. WEATHER DISCUSSION: Onshore flow brought a fresh surge of marine air into NW Oregon overnight with low clouds blanketing most of the Willamette Valley this morning. A strengthening upper-level ridge will warm the air aloft and clear the marine clouds from the valley this afternoon. Negatively-stacked onshore pressure gradients will struggle to balance-out this afternoon. Transport winds will back from NE to N this afternoon and possibly to the NNW late. TODAY'S FORECAST: Cloudy this morning; becoming sunny and warm this afternoon. Salem's high temperature today will be near 85?F (average is 82?F). Relative humidity: Dropping to 60% by noon and to near 30% by 5 p.m. Surface winds: N 5-10 mph. Transport winds: NNE 10 mph this morning; N 10 mph this afternoon. Mixing height: Rising to 3000 by noon and to near 4500 feet by 5 p.m. Salem's sunset tonight: 8:14 p.m. (Salem Airport data for Wednesday, August 16th: High 87?F; Rainfall: .00") (Maximum Ventilation Index expected today: 45) EXTENDED DISCUSSION: Friday should be mostly sunny with seasonal temperatures. A weak weather system will flatten the upper-level ridge and slightly increase the onshore flow late in the day. Expect morning marine clouds with sunny afternoons and seasonal temperatures this weekend. By Monday, the upper-level ridge will rebuild over the region, with only patchy morning clouds along the immediate coastline. Valley temperatures should climb back into the upper 80s. The upper-level ridge will progress eastward by mid-week. Increasing SW flow aloft will initiate a cooling trend and may create favorable burning 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. 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: 36352 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Aug 17 11:58:47 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 17 Aug 2017 18:58:47 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT THU AUG 17, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from noon until 2 p.m. with a 50 acre limit. WEATHER DISCUSSION: Onshore flow brought a fresh surge of marine air into NW Oregon overnight. Morning low clouds are currently in the process of clearing from the valley. A strengthening upper-level ridge will bring sunshine and warm temperatures this afternoon. Negatively-stacked onshore pressure gradients will struggle to balance-out today. Transport winds should be mostly northerly. TODAY'S FORECAST: Becoming sunny and warm this afternoon. Salem's high temperature today will be near 85?F (average is 82?F). Relative humidity: Near 60% now; dropping to near 30% by 5 p.m. Surface winds: N 5-10 mph. Transport winds: N 8-13 mph this afternoon. Mixing height: Near 3000 now; rising to near 4500 feet by 5 p.m. Salem's sunset tonight: 8:14 p.m. (Salem Airport data for Wednesday, August 16th: High 87?F; Rainfall: .00") (Maximum Ventilation Index expected today: 60) EXTENDED DISCUSSION: Any morning clouds will be brief on Friday. A weak weather system will flatten the upper-level ridge in the afternoon, slightly increasing the onshore flow and capping high temperatures in the mid-80s. Expect morning marine clouds and afternoon sunshine this weekend with high temperatures in the low-80s. By Monday, a building upper-level ridge will bring sunny skies with temperatures warming into the upper 80s. The upper-level ridge will progress eastward by mid-week. Increasing SW flow aloft will bring cooler temperatures and possible 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. 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: 36352 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Aug 18 08:57:29 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 18 Aug 2017 15:57:29 +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 AUG 18, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: An upper-level ridge has weakened the onshore flow, so any patchy morning clouds will be brief today. A weak weather system will flatten the upper-level ridge in the afternoon, slightly increasing the onshore flow and capping high temperatures in the mid-80s. We may see some high clouds in the afternoon, and an influx of marine low clouds is likely overnight. TODAY'S FORECAST: Sunny and seasonably warm. Turning a little breezy this afternoon. Salem's high temperature today will be near 84?F (average is 82?F). Relative humidity: Dropping to 60% by 11 a.m. and to near 30% by 5 p.m. Surface winds: N 5-10 mph this morning; NNW 10-15 mph this afternoon. Transport winds: NNE 10 mph this morning; NNW 15 mph this afternoon. Mixing height: Rising to 3000 about noon and to near 4500 feet by 5 p.m. Salem's sunset tonight: 8:13 p.m. (Salem Airport data for Thursday, August 17th: High 85?F; Rainfall: .00") (Maximum Ventilation Index expected today: 70) EXTENDED DISCUSSION: Expect morning marine clouds and afternoon sunshine this weekend with high temperatures in the low-80s. By Monday, a building upper-level ridge will inhibit morning clouds. Sunny skies and warmer air aloft will allow temperatures to climb to near 90?F. The ridge will progress eastward with increasing SW flow aloft initiating a cooling trend at mid-week. Tuesday will likely still be near 90?F, but increasing onshore flow should drop temperatures several degrees on Wednesday and may provide a burning opportunity. An upper-level trough will bring additional cooling Thursday and Friday. The eventual strength of the trough is still uncertain, but it may spread showers across much of Oregon. 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. 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: 36352 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Aug 18 11:54:49 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 18 Aug 2017 18:54:49 +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 AUG 18, 2017 *** Next Update 9 a.m. Tuesday, August 22nd *** BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A weak weather system may spread some high clouds across the region today, but its main effect will be to increase the onshore flow. That should cap afternoon temperatures in the middle-80s and push a fresh surge of marine air into the valley overnight. TODAY'S FORECAST: Sunny and seasonably warm. Turning a little breezy this afternoon. Salem's high temperature today will be near 84?F (average is 82?F). Relative humidity: Dropping to near 30% by 5 p.m. Surface winds: N 8-15 mph this afternoon. Transport winds: N 15 mph this afternoon. Mixing height: Rising to 5000 feet by 5 p.m. Salem's sunset tonight: 8:13 p.m. (Salem Airport data for Thursday, August 17th: High 85?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: Expect morning marine clouds and afternoon sunshine this weekend with high temperatures in the low-80s. By Monday, a building upper-level ridge will inhibit morning clouds. Sunny skies and warmer air aloft will allow temperatures to climb to near 90?F. The ridge will progress eastward by Tuesday with developing SW flow aloft. Tuesday will likely still be near 90?F, but increasing onshore flow in the afternoon may provide a burning opportunity. Even stronger onshore flow should provide favorable burning conditions on Wednesday. An upper-level trough will bring additional cooling Thursday and Friday. The latest computer guidance has backed off on the strength of this system but still gives the Salem area a few light showers Thursday morning. 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. 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: 36352 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Aug 22 08:56:27 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 22 Aug 2017 15:56:27 +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 AUG 22, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: SE-S flow aloft pushed some wildfire smoke back over NW Oregon on Monday, after the eclipse, and nephelometer readings remain slightly elevated this morning. An upper-level ridge has shifted east of the state today, turning the winds aloft southwesterly. At the surface, a thermal trough remains over the valley this morning but should advance east of the Cascades this afternoon. The air aloft is quite warm, so mixing height will be slow to rise this afternoon. However, the combination of increasing onshore flow and SW winds aloft should begin to clear the wildfire smoke from the valley later this afternoon and could create favorable burning conditions. TODAY'S FORECAST: Sunny but hazy due to mostly-elevated wildfire smoke. Salem's high temperature today will be near 88?F (average is 82?F). Relative humidity: Dropping to 60% by 11 a.m. and to 30-35% by 5 p.m. Surface winds: SW 5 mph this morning; becoming NW 5-10 mph this afternoon. Transport winds: SW 5 mph this morning; becoming NW 5-12 mph this afternoon; shearing to SW at the mixing height. Mixing height: Rising to 3000 about 2 p.m. and to near 4000 feet by 5 p.m. Salem's sunset tonight: 8:06 p.m. (Salem Airport data for Monday, August 21st: High 90?F; Rainfall: .00") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: Increasing SW flow aloft and onshore flow at the surface should drop temperatures back to near average on Wednesday and may provide an afternoon burning opportunity. An upper-level trough will bring additional cooling on Thursday along with a chance of light showers. Any rainfall should be quite light. Temperatures will warm Friday through the weekend, with valley highs climbing back into the 90s by Sunday. 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 Aug 22 09:02:12 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 22 Aug 2017 16:02:12 +0000 Subject: [willamette-fcst] Corrected...Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT TUE AUG 22, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: SE-S flow aloft pushed some wildfire smoke back over NW Oregon on Monday, after the eclipse, and nephelometer readings remain slightly elevated this morning. An upper-level ridge has shifted east of the state today, turning the winds aloft southwesterly. At the surface, a thermal trough remains over the valley this morning but should advance east of the Cascades this afternoon. The air aloft is quite warm, so mixing height will be slow to rise this afternoon. However, the combination of increasing onshore flow and SW winds aloft should begin to clear the wildfire smoke from the valley later this afternoon and could create favorable burning conditions. TODAY'S FORECAST: Sunny but hazy due to mostly-elevated wildfire smoke. Salem's high temperature today will be near 88?F (average is 82?F). Relative humidity: Dropping to 60% by 11 a.m. and to 30-35% by 5 p.m. Surface winds: SW 5 mph this morning; becoming NW 5-10 mph this afternoon. Transport winds: SW 5 mph this morning; becoming NW 5-12 mph this afternoon; shearing to SW at the mixing height. Mixing height: Rising to 3000 about 2 p.m. and to near 4000 feet by 5 p.m. Salem's sunset tonight: 8:06 p.m. (Salem Airport data for Monday, August 21st: High 90?F; Rainfall: .00") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: Increasing SW flow aloft and onshore flow at the surface should drop temperatures back to near average on Wednesday and may provide an afternoon burning opportunity. An upper-level trough will bring additional cooling on Thursday along with a chance of light showers. Any rainfall should be quite light. Temperatures will warm Friday through the weekend, with valley highs climbing back into the 90s by Sunday. 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 Aug 22 11:57:37 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 22 Aug 2017 18:57:37 +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 TUE AUG 22, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The strong upper-level ridge responsible for the recent spell of warm weather is shifting east of the state. Increasing SW winds aloft appear to be clearing wildfire smoke from the northern coastal range and should slowly improve air quality over the valley. At the surface, a thermal trough has progressed into central Oregon with onshore flow developing west of the Cascades. Warm air aloft will keep mixing heights suppressed today, but the combination of increasing onshore flow and SW winds aloft could create favorable burning conditions. A PIBAL is scheduled for 2 p.m. TODAY'S FORECAST: Sunny but hazy, due to mostly-elevated wildfire smoke. Salem's high temperature today will be near 88?F (average is 82?F). Relative humidity: Dropping to 30-35% by 5 p.m. Surface winds: W 5 mph; becoming NW 5-10 mph this afternoon. Transport winds: W 5 mph; becoming NW 10-15 mph by late this afternoon; shearing to SW at the mixing height. Mixing height: Rising to 3000 about 2 p.m. and to near 4000 feet by 5 p.m. Salem's sunset tonight: 8:06 p.m. (Salem Airport data for Monday, August 21st: High 90?F; Rainfall: .00") (Maximum Ventilation Index expected today: 60) EXTENDED DISCUSSION: Increasing SW flow aloft and onshore flow at the surface should bring some morning marine clouds into the valley and drop temperatures back to near average on Wednesday. An afternoon burning opportunity is possible. An upper-level trough will bring additional marine clouds and cooling on Thursday along with a chance of light showers. Any rainfall should be quite light. Temperatures will warm Friday through the weekend, with valley highs climbing back into the 90s by Sunday. 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 Wed Aug 23 08:43:00 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 23 Aug 2017 15:43:00 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 23, 2017 Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:45 AM PDT WED AUG 23, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A transition in the weather pattern continues today, as a disturbance approaches the Oregon coast and creates W-SW flow aloft. This feature will cause mixing heights to begin rising rapidly after noon, and remain elevated into the early evening; potential field burning opportunities may remain open as well. Mid-valley gradients are already positively-stacked, and increasing onshore flow will create afternoon clouds over the Cascades. Mountain rain showers will fall over the Cascades and central Oregon, but the Silverton Hills will remain dry today. TODAY'S FORECAST: Partly Cloudy becoming Mostly Cloudy with Mountain Showers late this afternoon. Salem's high temperature today will be near 81?F (average is 83?F). Relative humidity: Below 60% by 10:30 a.m. and nearing 40% by 5 p.m. Surface winds: N 5-10 mph this morning, becoming NW 5-10 mph after 3 p.m. Transport winds: N 5-10 mph this morning, becoming NW 5-10 mph after 3 p.m. Mixing height: Rising to 3000 feet by 12 p.m. and above 5000 feet by 5 p.m. Salem's sunset tonight: 8:04 p.m. (Salem Airport data for Tuesday, August 22nd: High 89?F; Rainfall: .00") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: The weather pattern remains unstable on Thursday, as a storm system sweeps across southern Canada and a Cold Front with isolated rain showers drives across Washington in the morning hours. The Willamette Valley will be on the edge of this major feature, but most rainfall will occur north of Marion County. Onshore gradients and favorable mixing will be present all day, but elevated humidity and gusty winds will be limiting factors for field burning Thursday afternoon. Friday will see W flow aloft prevail in the wake of the storm, keeping onshore gradients favorable and clearing skies as the atmosphere begins to calm ahead of the weekend. Winds will remain W-NW, and lighten up enough to suggest field burning opportunities. The limiting factor will be moisture east of the Cascades, as any thundershowers could pause the gradient flow and slow the evacuation of smoke. Mild, sunny weather will persist for the weekend as an upper-level ridge moves into Oregon. The "Dog Days of Summer" will see temperatures rise above seasonal averages again, thanks to clear skies and declining humidity. Continued W flow aloft and onshore flow with afternoon sea breezes appear likely for the last few days of August, which may offer flexible field burning opportunities before Labor Day 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: 30720 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Aug 23 11:44:16 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 23 Aug 2017 18:44:16 +0000 Subject: [willamette-fcst] Field Burning Forecast - August 23, 2017 (Noon Update) Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT WED AUG 23, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A transition in the weather pattern continues today, as a disturbance approaches the Oregon coast and creates W-SW flow aloft. This feature will cause mixing heights to begin rising rapidly, and remain elevated into the early evening; potential field burning opportunities will may remain open as well. Mid-valley gradients remain positively-stacked, and increasing onshore flow will create afternoon clouds over the Cascades. Mountain rain showers will fall over the Cascades and central Oregon, but the Silverton Hills will remain dry today. TODAY'S FORECAST: Mostly Cloudy with Mountain Showers late this afternoon. Salem's high temperature today will be near 81?F (average is 83?F). Relative humidity: Below 60% now and nearing 40% by 5 p.m. Surface winds: N-NW 5-10 mph now, becoming NW 5-10 mph after 3 p.m. Transport winds: N-NW 5-10 mph now, becoming W-NW 5-10 mph after 3 p.m. Mixing height: Near 3000 feet currently and rising above 5000 feet by 5 p.m. Salem's sunset tonight: 8:04 p.m. (Salem Airport data for Tuesday, August 22nd: High 89?F; Rainfall: .00") (Maximum Ventilation Index expected today: 50) EXTENDED DISCUSSION: The weather pattern remains unstable on Thursday, as a storm system sweeps across southern Canada and a Cold Front with isolated rain showers drives across Washington in the morning hours. The Willamette Valley will be on the edge of this major feature, but most rainfall will occur north of Marion County. Onshore gradients and favorable mixing will be present all day, but elevated humidity and gusty winds will be limiting factors for field burning Thursday afternoon. Friday will see W flow aloft prevail in the wake of the storm, keeping onshore gradients favorable and clearing skies as the atmosphere begins to calm ahead of the weekend. Winds will remain W-NW, and lighten up enough to suggest field burning opportunities. The limiting factor will be moisture east of the Cascades, as any thundershowers could pause the gradient flow and slow the evacuation of smoke. Mild, sunny weather will persist for the weekend as an upper-level ridge moves into Oregon. The "Dog Days of Summer" will see temperatures rise above seasonal averages again, thanks to clear skies and declining humidity. Continued W flow aloft and onshore flow with afternoon sea breezes appear likely for the last few days of August, which may offer flexible field burning opportunities before Labor Day 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: 30720 bytes Desc: fbs.htm.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Aug 24 08:48:56 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 24 Aug 2017 15:48:56 +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 THU AUG 24, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from noon until 2 p.m. with a 50-acre limit. WEATHER DISCUSSION: An upper-level trough brought increasing SW flow aloft and onshore flow at the surface on Wednesday, forcing marine air into the valley overnight. The marine layer is about 5000 feet thick, so morning low clouds could produce some sprinkles. Another weak upper-level trough should help to break up the marine clouds this afternoon and keep the air aloft cool enough for excellent daytime mixing. Even with afternoon sunshine, valley temperatures will struggle to reach 80?F. The limiting factors for burning today will be negatively-stacked pressure gradients and mostly northerly winds. TODAY'S FORECAST: Cloudy with a chance of sprinkles this morning. Clearing this afternoon. Salem's high temperature today will be near 78?F (average is 82?F). Relative humidity: Dropping to 60% by noon and to 40% by 5 p.m. Surface winds: N 5-10 mph. Transport winds: N 10-15 mph. Mixing height: Rising to 3000 by noon and to near 5000 feet by 5 p.m. Salem's sunset tonight: 8:03 p.m. (Salem Airport data for Wednesday, August 23rd: High 85?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: A building upper-level ridge will warm temperatures into the low-80s on Friday. Warming aloft will begin to suppress daytime mixing with mostly northerly transport winds. A strong ridge is expected to warm temperatures to near 90?F on Saturday and the mid-90s Sunday and Monday. In addition, the winds aloft will turn more southerly, likely transporting wildfire smoke back into the region. A very weak upper-level trough should turn the flow aloft southwesterly again next Tuesday, which will help to clear any wildfire smoke from the valley. Increasing onshore flow is expected to cool temperatures into the 80s and may create mid-week 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: 37376 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Aug 24 11:58:08 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 24 Aug 2017 18:58:08 +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 AUG 24, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from noon until 2 p.m. with a 50-acre limit. WEATHER DISCUSSION: An incoming weak upper-level trough began breaking up the marine low clouds over the northern Willamette valley late this morning. Continued clearing is expected this afternoon, but cool air aloft should cap high temperatures near 80?F. Mixing will be excellent today, but negative gradient stacking, as a result of last night's "marine push," will be difficult to balance. NE transport winds should turn northerly this afternoon. There is a slight chance they will back to the NW but could become too brisk for good plume development. The bottom line is that a brief burning "window" is possible but unlikely late this afternoon. A PIBAL is scheduled for 3 p.m. TODAY'S FORECAST: Partly cloudy, cooler, and breezy. Salem's high temperature today will be near 78?F (average is 82?F). Relative humidity: Dropping to 40% by 5 p.m. Surface winds: NE 5-10 mph; becoming N 7-15 mph. Transport winds: NE 10-15 mph; becoming N 15 mph. Mixing height: Rising to near 5000 feet by 5 p.m. Salem's sunset tonight: 8:03 p.m. (Salem Airport data for Wednesday, August 23rd: High 85?F; Rainfall: .00") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: A building upper-level ridge will warm temperatures into the low-80s on Friday. Warming aloft will begin to suppress daytime mixing. Transport winds will likely stay too northerly to allow for burning. A strong ridge is expected to warm temperatures to near 90?F on Saturday and the mid-90s Sunday and Monday. In addition, the winds aloft will turn more southerly and may transport wildfire smoke back into the region. A very weak upper-level trough should turn the flow aloft southwesterly again next Tuesday, which will help to clear any wildfire smoke from the valley. Increasing onshore flow is expected to cool temperatures into the mid-80s during the second half of next week and may 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 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 Aug 25 08:56:03 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 25 Aug 2017 15:56:03 +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 AUG 25, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from noon until 2 p.m. with a 50-acre limit. WEATHER DISCUSSION: Onshore flow weakened overnight, and pressure gradients have turned mostly northerly this morning. An upper-level ridge of high pressure will begin building over the region today. As a result, a full day of sunshine is expected today with valley temperatures warming back into the low 80s. Warming aloft will likely cap mixing heights just under 5000 feet this afternoon. Mostly northerly winds should increase this afternoon. TODAY'S FORECAST: Sunny, warmer, and breezy. Salem's high temperature today will be near 83?F (average is 81?F). Relative humidity: Dropping to 50% by noon and to 30% by 5 p.m. Surface winds: N 5-10 mph this morning; N 10-15 mph this afternoon. Transport winds: NNE 10-15 mph this morning; N 14-18 mph this afternoon. Mixing height: Rising to 3000 by noon and to near 4800 feet by 5 p.m. Salem's sunset tonight: 8:01 p.m. (Salem Airport data for Thursday, August 24th: High 78?F; Rainfall: .00") (Maximum Ventilation Index expected today: 86) EXTENDED DISCUSSION: A strong upper-level ridge is expected to warm temperatures to near 90?F on Saturday and the mid-90s Sunday and Monday. In addition, offshore flow will likely transport wildfire smoke back into the region. A very weak upper-level trough should turn winds onshore next Tuesday and Wednesday, which will bring some cooling, help to clear any wildfire smoke from the valley, and possibly create burning opportunities. Another strong upper-level ridge is expected to build over the region later next week, with very warm temperatures and possibly more wildfire smoke. 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 Fri Aug 25 11:49:13 2017 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 25 Aug 2017 18:49:13 +0000 Subject: [willamette-fcst] Silverton Hills Midday Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:45 AM PDT FRI AUG 25, 2017 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is allowed from noon until 2 p.m. with a 50-acre limit. WEATHER DISCUSSION: A strengthening upper-level ridge will bring sunny and warmer weather today. Mixing will be good, but increasing northerly winds make field-burning unlikely. No PIBALS are planned for this afternoon, but the weather will be monitored for any changes that could create a burning opportunity. TODAY'S FORECAST: Sunny, warmer, and breezy. Salem's high temperature today will be near 83?F (average is 81?F). Relative humidity: Dropping to 30% by 5 p.m. Surface winds: N 10-15 mph. Transport winds: N 14-18 mph. Mixing height: Rising to near 4800 feet by 5 p.m. Salem's sunset tonight: 8:01 p.m. (Salem Airport data for Thursday, August 24th: High 78?F; Rainfall: .00") (Maximum Ventilation Index expected today: 86) EXTENDED DISCUSSION: A strong upper-level ridge is expected to warm temperatures to near 90?F on Saturday and the mid-90s Sunday and Monday. Offshore flow will likely bring wildfire smoke back into the region, effectively blocking some sunlight from reaching the surface, or temperatures would be even warmer. A dry and weak upper-level trough should bring some cooling and help to clear wildfire smoke from the valley Tuesday and Wednesday. Weak onshore flow may create burning opportunities. The upper-level ridge is expected strengthen later next week, with the likely return of very warm temperatures and wildfire smoke to the region. 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: 36352 bytes Desc: Silverton Hills Midday Forecast_Pete.doc URL: