From willamette-fcst at listsmart.osl.state.or.us Tue Sep 3 08:42:51 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 3 Sep 2013 08:42:51 -0700 Subject: [willamette-fcst] Silverton Hills Field Burning Forecast Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT TUE SEP 3, 2013 BURN ADVISORY: Recommended burn times for agricultural burning are from 12:00pm to 5:30pm. WEATHER DISCUSSION: Upper level low continues to spin around off the Pacific Northwest coast this morning. This low is rotating variable clouds with a few sprinkles up from the south. Surface pressure gradients are weak this morning with an onshore pressure gradient of 1.8 mb from Newport to Salem and an onshore gradient of 0.2 mb from Salem to Redmond. The morning sounding shows moderately stable conditions with very light SW to W winds. The upper low will remain in place today bringing continued variable clouds over the region. The pressure gradient will slowly become more onshore today due to inland afternoon heating. Mixing levels should rise to near 5000 ft by mid to late afternoon. (Salem Airport data for Monday, Sept. 2nd: High 80?F; Rainfall .00") (Maximum Ventilation Index expected today: 35) TODAY'S FORECAST: Partly to mostly cloudy. Salem's high temperature today will be near 80. Relative humidity drops to 50% around noon. Minimum RH near 40%. Surface winds: Light and variable, favoring S to W flow during the morning to early afternoon. SW to W at 3-7 mph during the afternoon. Transport winds: Light and variable, favoring S to W flow during the morning. SSW to W at 4-8 mph during the afternoon. Maximum mixing height: 5000 ft. Sunset tonight: 7:45 p.m. EXTENDED DISCUSSION: Upper level low weakens a little tonight through Wednesday morning then energizes and starts moving inland later Wednesday. Expect continued variable clouds with an increase of clouds later tomorrow with a chance of showers tomorrow evening. Air mass will stay about the same with minor stability during the morning becoming unstable during the afternoon with mixing heights rising above 5000 ft. Wind flow will be complicated with winds below 3000 ft NW to N but SE to S above 3000 ft. Upper level low moves into the state early Thursday bringing some showers throughout western Oregon. The low will then move to the northeast and weaken Friday. Showers should decrease by Thursday evening. Expect cloudy skies Friday morning with clearing during the afternoon. Wind flow will be mostly SW to NW. Moisture will likely preclude burning opportunities for Thursday but drying on Friday may open up a burn opportunity. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15mph. 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 times the transport wind speed 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Nick Yonker ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 3 11:46:18 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 3 Sep 2013 11:46:18 -0700 Subject: [willamette-fcst] Silverton Hills Field Burning Forecast - Noon Update Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 12:00 PM PDT TUE SEP 3, 2013 BURN ADVISORY: Recommended burn times for agricultural burning are from 12:00pm to 5:30pm. WEATHER DISCUSSION: Upper level low continues to spin around off the Pacific Northwest coast today bringing variable clouds up from the south. Surface pressure gradients are lightly onshore with the gradient from Newport to Salem at 1.7 mb and the gradient 1.4 mb onshore from Salem to Redmond. The upper low will remain in place today bringing continued variable clouds over the region. The pressure gradient will slowly become more onshore this afternoon due to inland heating. Gradient stacking may be near neutral however between the Coast Range and Cascades. Mixing levels should rise to near 5000 ft by mid to late afternoon. (Salem Airport data for Monday, Sept. 2nd: High 80?F; Rainfall .00") (Maximum Ventilation Index expected today: 35) TODAY'S FORECAST: Partly to mostly cloudy. Salem's high temperature today will be near 80. Relative humidity drops to near 40% around 4 p.m. Surface winds: Light and variable, favoring S to W flow during the morning to early afternoon. SW to W at 3-7 mph during the afternoon. Transport winds: Light and variable, favoring S to W flow during the morning. SSW to W at 4-8 mph during the afternoon. Maximum mixing height: 5000 ft. Sunset tonight: 7:45 p.m. EXTENDED DISCUSSION: Upper level low weakens a little tonight through Wednesday morning then energizes and starts moving inland later Wednesday. Expect continued variable clouds with an increase of clouds later tomorrow with a chance of showers or thundershowers tomorrow evening. Air mass will stay about the same with minor stability during the morning becoming unstable during the afternoon with mixing heights rising above 5000 ft. Wind flow will be complicated with wind below 3000 ft NW to N but SE to S above 3000 ft. Upper level low moves into the state early Thursday bringing showers throughout western Oregon. The low will then move to the northeast and weaken Friday. Showers should decrease by Thursday evening to Friday morning. Expect cloudy skies Friday morning with some clearing during the afternoon. Wind flow will be mostly SW to NW. Moisture will likely preclude burning opportunities for Thursday and slow drying may prevent burn opportunities on Friday as well. 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 15mph. 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 times the transport wind speed 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Nick Yonker ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 4 08:46:31 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 4 Sep 2013 08:46:31 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT WED SEP 4, 2013 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The upper level low continues to spin off the Pacific Northwest coast this morning bringing cloudy conditions and deep southerly winds aloft to the region. Surface pressure gradients are weakly favorable this morning but winds are very weak. The upper low will edge just a bit closer today, and as a result mostly cloudy conditions should dominate over the region with surface temperatures a bit cooler than yesterday and some isolated showers over the Silverton Hills. Pressure gradients will slowly increase onshore this afternoon due to inland heating, and weak northwesterly surface winds are expected late today. Gradient stacking may be a factor though late as the pressure gradient from Salem to Redmond will increase this afternoon. Mixing levels should again rise to near 5000 ft by mid- to late-afternoon. (Salem Airport data for Tues., Sept. 3rd: High 83?F; Rainfall .00") (Maximum Ventilation Index expected today: 35) TODAY'S FORECAST: Mostly cloudy with weak surface winds and some late-day isolated showers. Salem's high temperature today will be near 80. Relative humidity drops to near 40% during mid-afternoon. Surface winds: Light and variable, becoming NW 5-10 during the afternoon. Transport winds: Light and variable, becoming NW 5-10 during the afternoon. Maximum mixing height: 5000 ft. Sunset tonight: 7:43 p.m. EXTENDED DISCUSSION: The upper level low energizes and moves inland on Thursday, centered just south of the Silverton Hills creating widespread showers and thunderstorms and cooler conditions. Significant wetting rains are expected by mid-afternoon. Expect mixing heights of 2500-3500 feet with northwesterly transport winds increasing during the day. The low will continue to move to the east on Friday, leaving cool temperatures and wet fields. Expect cloudy skies Friday morning with some clearing during the afternoon. Wind flow will be mostly N to NW. Cloudy skies are also expected early on Saturday, but with clearing during the afternoon and warmer 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 15mph. 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 times the transport wind speed 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 4 11:48:48 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 4 Sep 2013 11:48:48 -0700 Subject: [willamette-fcst] Silverton Hills Midday Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 12:00 PM PDT WED SEP 4, 2013 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The upper level low continues to spin off the Pacific Northwest coast today, bringing cloudy conditions and deep southerly winds aloft to the region. Locally, surface pressure gradients are 2.0 mb Newport-Salem and 1.9 Salem-Redmond. The latter may increase significantly this afternoon and cause some local downward motion which would not be favorable for burning. However, large-scale upward motion is expected to offset this to some degree. Mostly cloudy conditions have dominated over the region so far today, and this is expected to continue through the afternoon. Thus far scattered showers have been confined to west of the region; however, some isolated showers over the Silverton Hills are expected. Currently, surface winds are weak S to SW, but this is expected to switch to weak W-NW late today. Mixing levels, currently above 3000 feet, should continue to rise and get to 4500 ft by mid- to late-afternoon. (Salem Airport data for Tues., Sept. 3rd: High 83?F; Rainfall .00") (Maximum Ventilation Index expected today: 35) TODAY'S FORECAST: Mostly cloudy with weak surface winds and some late-afternoon isolated showers. Salem's high temperature today will be near 80. Relative humidity drops to 40-45% by mid-afternoon. Surface winds: S to SW 3-7 mph becoming W-NW 5-10 during the afternoon. Transport winds: Light and variable, becoming NW 5-10 during the afternoon. Maximum mixing height: 4500 ft. Sunset tonight: 7:43 p.m. EXTENDED DISCUSSION: The upper level low energizes and moves inland on Thursday, centered over southwestern OR during the afternoon, likely creating widespread showers and thunderstorms and cooler conditions for the Silverton Hills. Significant wetting rains are expected by mid-afternoon or earlier. Expect mixing heights of 2000-3000 feet with W to NW transport winds increasing during the day. The low will continue to move to the northeast on Friday, leaving cool temperatures and wet fields. Expect cloudy skies Friday morning with some clearing during the afternoon. Wind flow will be mostly NW to W. Cloudy skies are also expected early on Saturday, but clearing should take over during the afternoon with warmer 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 15mph. 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 times the transport wind speed 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 5 08:38:39 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 5 Sep 2013 08:38:39 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT THU SEP 5, 2013 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The upper level low is finally making its way northeast into southwestern OR today. Overnight rain amounts in the area ranged from about 0.05 to 0.15" and have likely left fields wet. The residual moisture will not dry out today as the upper low is going to cause mostly cloudy, cooler and showery conditions all day. (Salem Airport data for Wed., Sept. 4th: High 77?F; Rainfall T) (Maximum Ventilation Index expected today: 20) TODAY'S FORECAST: Mostly cloudy with weak surface winds and scattered showers and thunderstorms this afternoon. Wetting rains are likely over the Silverton Hills. Salem's high temperature today will be in the low 70s. Relative humidity drops to 60-65% by mid-afternoon. Surface winds: Light and variable, becoming W-NW 5-10 during the afternoon. Transport winds: Light and variable, becoming NW 10-15 during the afternoon. Maximum mixing height: 2500 ft. Sunset tonight: 7:41 p.m. EXTENDED DISCUSSION: The low will continue to move off to the northeast on Friday, leaving cool temperatures, light showers at least through the morning, and wet fields. Expect cloudy skies Friday morning with some clearing during the afternoon. Wind flow will be mostly W to NW. Very little field drying is expected during the afternoon. Cloudy skies are also expected early on Saturday, but clearing should take over during the afternoon with warmer conditions and mostly N winds. The drying trend will continue on 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 15mph. 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 times the transport wind speed 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 5 11:42:01 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 5 Sep 2013 11:42:01 -0700 Subject: [willamette-fcst] Silverton Hills Midday Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 12:00 PM PDT THU SEP 5, 2013 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: The upper level low is making its way northeast into southwestern OR today. Residual moisture from last night's rain will not dry out today as the upper low is causing cloudy skies, and widespread showers will develop later. (Salem Airport data for Wed., Sept. 4th: High 77?F; Rainfall T) (Maximum Ventilation Index expected today: 25) TODAY'S FORECAST: Mostly cloudy with weak surface winds and numerous showers and thunderstorms developing this afternoon. Wetting rains are likely over the Silverton Hills. Salem's high temperature today will be in the low 70s. Relative humidity drops to 55-60% this afternoon. Surface winds: Light and variable, becoming W-NW 5-10 mph by mid-afternoon. Transport winds: Light and variable, becoming NW 10-15 during the afternoon. Maximum mixing height: 2500 ft. Sunset tonight: 7:41 p.m. EXTENDED DISCUSSION: The low will continue to move off to the northeast on Friday, leaving cool temperatures, light showers at least through the morning, and wet fields. Expect cloudy skies Friday morning with some clearing possible during the afternoon. Wind flow will be mostly W to NW. Very little field drying is expected during the afternoon. Cloudy skies are also expected early on Saturday, but clearing should take over during the afternoon with mostly N winds. The drying trend will continue on Sunday accompanied by warming. 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 15mph. 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 times the transport wind speed 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: Silverton Hills Midday Forecast_doug.doc Type: application/msword Size: 30720 bytes Desc: Silverton Hills Midday Forecast_doug.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 6 08:36:39 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 6 Sep 2013 08:36:39 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT FRI SEP 6, 2013 BURN ADVISORY: Recommended times for agricultural burning are 1:00 p.m. to 5:30 p.m.. Prep burning is not allowed. WEATHER DISCUSSION: The upper level low is exiting the region today, leaving cool temperatures and south to southwest winds. After yesterday's flooding rains, fields will remain wet for several days. Expect scattered light showers and generally southwest to west winds today. (Salem Airport data for Thurs., Sept. 5th: High 71?F; Rainfall 1.82") (Maximum Ventilation Index expected today: 30) TODAY'S FORECAST: Cloudy with southwesterly surface winds and scattered light showers. Salem's high temperature today will be around 70. Relative humidity drops to 60-65% this afternoon. Surface winds: S 10-15 mph, becoming SW-W 5-15 mph by afternoon. Transport winds: SW 10-20. Maximum mixing height: 2500 ft. Sunset tonight: 7:39 p.m. EXTENDED DISCUSSION: Cloudy skies are also expected early on Saturday, but clearing should take over during the afternoon with mostly N winds and temperatures well up into the 70s. The drying trend will continue on Sunday accompanied by more warming. For early next week, warm and dry conditions are expected to continue with highs potentially getting up into the 80s in the Silverton Hills. 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 15mph. 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 times the transport wind speed 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 9 08:47:56 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 9 Sep 2013 08:47:56 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT MON SEP 9, 2013 BURN ADVISORY: Agricultural Burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strengthening offshore upper-level ridge of high pressure will produce dry and stable northerly flow aloft over Oregon today. The morning sounding over Salem showed several degrees of warming, compared to 24 hours ago, from just above the surface up to 10,000 feet. That will make for lower daytime mixing heights today. Satellite imagery shows marine low clouds penetrating up the Columbia River into the northern Willamette Valley; extending about as far south as the Silverton Hills. At the surface, a thermal trough will build northward along the Oregon coast today, with increasing north to NE winds in the Willamette Valley this afternoon. Any morning clouds should quickly give way to sunny skies, with afternoon temperatures climbing to well above average. The combination of lowering humidity and increasing north winds may put the valley into State Fire Marshal Burn-Ban conditions late in the day. TODAY'S FORECAST: Patchy morning clouds. Sunny and warm again this afternoon. Salem's high temperature today will be near 87 degrees (normal is 79). Relative humidity: Drops below 60% by 11 a.m. and to near 30% by 5 p.m. Surface winds: N 6-12 by late this morning; increasing to N 10-15, with gusts to around 20 mph, this afternoon. Transport winds: NNE 10 mph this morning; becoming NNE 20 mph this afternoon. Mixing height: Rising to 3000 feet by 2 p.m. and to 4000 feet by 5 p.m. Salem's sunset tonight: 7:33 p.m. (Salem Airport data for Sunday, Sept. 8th: High 87?F; No Rain) (Maximum Ventilation Index expected today: 80) EXTENDED DISCUSSION: A strong ridge of high pressure will build over Oregon Tuesday and Wednesday, with the coastal thermal trough moving over the Willamette Valley. That will bring progressively warmer weather, with high temperatures likely climbing into the low-to-mid 90s. North winds will slacken, but the combination of warm temperatures and low humidity could put the valley into State Fire Marshal Burn-Ban conditions in the afternoons. Late this week, some of the long-range computer models weaken the upper-level ridge enough to switch the low-level winds onshore. That could create a burning opportunity, but confidence is low at this time. A more significant change to a cooler onshore flow pattern is advertised for 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. 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: 32256 bytes Desc: Silverton Hills AM Forecast_Pete.doc URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 10 08:37:47 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 10 Sep 2013 08:37:47 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT TUE SEP 10, 2013 BURN ADVISORY: Agricultural burning north of Salem: recommended burn times are from noon until 5:30 p.m. Agricultural burning from Salem south is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strengthening upper-level ridge of high pressure will produce dry and stable NE flow aloft over Oregon today. The morning sounding over Salem showed unseasonably warm air above a relatively cool marine layer extending from the surface up to about 2500 feet. That will keep maximum mixing heights suppressed to only near 3000 feet this afternoon. Satellite imagery shows a narrow band of marine low clouds extending down the length of the Willamette valley this morning, mainly along the Cascade foothills. At the surface, a thermal trough is building northward along the Oregon coast. A drying NE flow across western Oregon, below about 5000 feet, should help to evaporate the marine clouds by midday, with valley temperatures climbing into the low 90s by late this afternoon. Increasingly dry NNE winds could put the valley into State Fire Marshal Burn-Ban conditions late this afternoon, but elevated surface dew-point temperatures, due to recent heavy rains, may keep humidity levels above 30%. TODAY'S FORECAST: Morning clouds; Sunny and warmer this afternoon. Salem's high temperature today will be near 92 degrees (normal is 79). Relative humidity: Drops below 60% by noon and to near 30% by 5 p.m. Surface winds: NNE 6-10 this morning; increasing to NNE 7-15 this afternoon. Transport winds: NE 5-10 mph this morning; becoming NE 15 mph this afternoon. Mixing height: Rising to 2500 feet by noon and to about 3200 feet by 5 p.m. Salem's sunset tonight: 7:32 p.m. (Salem Airport data for Monday, Sept. 9th: High 84?F; No Rain) (Maximum Ventilation Index expected today: 48) EXTENDED DISCUSSION: A strong ridge of high pressure will remain over Oregon on Wednesday, with the coastal thermal trough moving over the Willamette Valley. That will warm valley temperatures into the mid 90s. North winds will slacken, but the combination of warm temperatures and lowering humidity levels could put the valley into State Fire Marshal Burn-Ban conditions Wednesday afternoon. The surface thermal trough is forecast to shift into central Oregon on Thursday and eastern Oregon on Friday. That will initiate a slow cooling trend, with high temperatures backing off into the mid to upper 80s by Friday. Transport winds may turn enough onshore to allow for the burning of any remaining fields, but details remain uncertain. A more significant change to an autumn-like onshore flow pattern is advertised for 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 11 08:53:36 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 11 Sep 2013 08:53:36 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT WED SEP 11, 2013 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong ridge of high pressure is over Oregon today. At the surface, a thermal trough extends from the southwestern interior of Oregon to over the northern coast range. In response to the shifting trough position, onshore flow has forced marine low clouds and much cooler temperatures onto the coast and into the central and southern coastal range. However, low-level offshore winds are keeping skies clear, and temperatures unseasonably warm, over the interior of western Oregon and across the northern coast range. Mixing heights will be quite low today, due to exceptionally warm air aloft. Winds at the top of the mixing layer will be southeasterly, which is not a favorable pattern for burning. The upper-level ridge will slowly progress northeastward, to over eastern Washington and northern Idaho, this afternoon. The surface thermal trough will shift over the Willamette Valley and possibly as far east as the Cascades. Today should be the warmest day of this hot spell with valley temperatures climbing into the mid 90s. State Fire Marshal Burn-Ban conditions will be approached this afternoon, but relative humidity levels will likely remain just above 30%. TODAY'S FORECAST: Sunny; near-record warm temperatures; light winds. Salem's high temperature today will be near 94 degrees (normal is 78). Relative humidity: Drops below 60% by 11 a.m. and to near 40% by 5 p.m. Surface winds: Var 2-6 mph this morning; becoming SW 2-6 mph this afternoon. Transport winds: Var 2-6 mph; possibly turning SW 2-6 mph this afternoon. Mixing height: Rising to only about 2000 feet by 5 p.m. Salem's sunset tonight: 7:30 p.m. (Salem Airport data for Tuesday, Sept. 10th: High 92?F; Rainfall .00") (Maximum Ventilation Index expected today: 12) EXTENDED DISCUSSION: The surface thermal trough is forecast to shift into central Oregon on Thursday and eastern Oregon on Friday. That will initiate a slow cooling trend, with high temperatures backing off into the mid to upper 80s by Friday. Burning conditions will not be optimal either day, but northwesterly transport winds should allow for the burning of the few remaining fields, especially by Friday, which is timely considering the outlook for next week. An upper-level trough is forecast to increase the southerly flow aloft over the weekend, with showers and thundershowers likely by Sunday. A damp and much cooler onshore flow pattern should bring autumn-like weather 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 12 08:41:54 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 12 Sep 2013 08:41:54 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT THU SEP 12, 2013 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong ridge of high pressure persists over western Oregon today. Low cloud coverage is extensive this morning, but clearing is expected later this morning. Warmer than average temperatures and dry conditions continue. Mixing heights will continue to be quite low today, due to warm air aloft. Winds through the mixed layer and aloft will become weak northeasterly, which is not a favorable pattern for burning either. Low-level wind may shift to NNW late this afternoon. Slightly cooler high temperatures are expected. TODAY'S FORECAST: Becoming sunny with warm temperatures continuing and light winds. Salem's high temperature today will be near 88 degrees (average is 78). Relative humidity: Drops below 65% by 11 a.m. and to near 35% by 5 p.m.. Surface winds: Very light this morning; becoming N to NNW 5-10 mph this afternoon. Transport winds: Becoming N 5-10 mph by this afternoon and NNW 5-10 mph late afternoon. Mixing height: Rising to only about 2000 feet by 5 p.m. Salem's sunset tonight: 7:28 p.m. (Salem Airport data for Wed., Sept. 11: High 96?F; Rainfall .00") (Maximum Ventilation Index expected today: 15) EXTENDED DISCUSSION: The upper ridge will begin to weaken on Friday, but dry and unseasonably warm conditions will continue in the low levels. Generally, burning conditions will not be optimal with limited mixing heights, but late-day northwesterly transport winds may allow for some burning. An approaching upper-level trough is forecast to increase the southerly flow aloft over the weekend. Dry conditions but with some clouds are expected for Saturday, and then showers and thunderstorms are likely by Sunday accompanied with a return to cooler temperatures. An unsettled and much cooler onshore flow pattern should bring autumn-like weather for much of next week. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 13 08:39:46 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 13 Sep 2013 08:39:46 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT FRI SEP 13, 2013 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. WEATHER DISCUSSION: A strong ridge of upper high pressure persists over western Oregon today. Low cloud coverage is extensive this morning, but clearing is expected later this morning. Warmer than average temperatures and dry conditions continue. A few clouds from a weak upper low well to the southeast may sneak into the picture this afternoon, but otherwise sunny conditions will continue. Mixing heights will continue to be relatively low by summer standards today, due to continued warm air aloft. Winds through the mixed layer will become weak northerly, which is not a favorable pattern for burning either. Slightly cooler high temperatures are expected. TODAY'S FORECAST: Becoming mostly sunny with warm temperatures continuing and light winds. Salem's high temperature today will be in the low 80s (average is 78). Relative humidity: Drops below 70% by 11 a.m. and to near 40% by 5 p.m.. Surface winds: Very light this morning; becoming N to NNW 5-10 mph this afternoon. Transport winds: Becoming NNW 5-10 mph by this afternoon. Mixing height: Rising to 2000-2500 feet by 5 p.m. Salem's sunset tonight: 7:26 p.m. (Salem Airport data for Thurs., Sept. 12: High 85?F; Rainfall .00") (Maximum Ventilation Index expected today: 15-20) EXTENDED DISCUSSION: The upper ridge continues to weaken and by Saturday afternoon an approaching upper-level trough is forecast to increase the southerly flow aloft. Dry conditions will continue Saturday but with early low clouds and some afternoon increase in upper clouds. Then, showers and thunderstorms are likely by afternoon on Sunday with deep southeasterly winds and a marked cooling trend. An unsettled and much cooler onshore flow pattern should bring unsettled autumn-like weather for much of next week, including the daily chance of early clouds over the valley and Silverton Hills. 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 16 08:57:38 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 16 Sep 2013 08:57:38 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT MON SEP 16, 2013 BURN ADVISORY: Recommended times from agricultural burning are from 1 p.m. until 5:30 p.m. WEATHER DISCUSSION: A strengthening southwesterly flow aloft deepened the marine air mass across western Oregon overnight. The Salem sounding this morning showed generally southwesterly flow extending from just above the surface up through a 6000-foot deep marine layer. Mostly cloudy skies extend from the coast to the crest of the Cascades, but there is little to no shower activity on radar. Some breaks in the marine clouds today should allow surface temperatures to climb into the low 70s. With quite cool air aloft, even limited surface heating will allow mixing heights to rise above 5000 feet later today. Favorable gradient-stacking and southwesterly transport winds may allow for the burning of any remaining fields this afternoon, with relative humidity levels dropping below 60 percent. There is only a slight chance of sprinkles or a light shower. TODAY'S FORECAST: Mostly cloudy. Possible sprinkles or very light showers. Salem's high temperature today will be near 72 degrees (normal is 77). Relative humidity: Drops to 60% by 2 p.m. and to near 55% by 5 p.m. Surface winds: S 5-10 mph this morning; SW 5-10 mph this afternoon. Transport winds: SW 10 mph; veering to W 10 mph later this afternoon. Mixing height: Rising to 3000 feet by 1 p.m. and to near 6000 feet by 5 p.m. Salem's sunset tonight: 7:20 p.m. (Salem Airport data for Sunday, Sept. 15th: High 69?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 60) EXTENDED DISCUSSION: Continued southwesterly flow aloft will direct a weak weather system onshore Tuesday, with showers likely across the northern and central Willamette Valley. Rainfall amounts should be less than one-quarter of an inch. Drier and warmer conditions are expected Wednesday and Thursday, as an upper-level ridge moves over the region. Temperatures should recover to slightly above normal by Thursday. Wet weather may return by Friday. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 17 08:27:48 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 17 Sep 2013 08:27:48 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT TUE SEP 17, 2013 BURN ADVISORY: Recommended times for agricultural burning are from 10 a.m. until 5:30 p.m. WEATHER DISCUSSION: Southwesterly flow aloft is directing a weak upper-level disturbance across the state today. Satellite imagery is showing mostly cloudy skies statewide, but most of the shower activity is south of a line from Newport to Corvallis to Madras. A few showers are likely to develop over the northern Willamette Valley this afternoon with high temperatures 5-10 degrees below average. The air aloft is still unseasonably cool today, so afternoon mixing heights are likely to rise to near 5000 feet. Rainfall totals in the Silverton Hills should be less than one-tenth of an inch with some areas possibly staying completely dry. If fields remain dry, onshore transport winds will be favorable for burning again today, should the need arise. TODAY'S FORECAST: Mostly cloudy. A few light showers possible. Salem's high temperature today will be near 69 degrees (normal is 77). Relative humidity: Drops below 60% by noon and to near 50% by 5 p.m. Surface winds: NW 5-10 mph this morning; WNW 7-13 mph this afternoon. Transport winds: NW 10 mph this morning; NW 15 mph this afternoon. Mixing height: Rising to 3000 feet by 11 a.m. and to near 5000 feet by 5 p.m. Salem's sunset tonight: 7:18 p.m. (Salem Airport data for Monday, Sept. 16th: High 72?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: A transitory upper-level ridge will bring drier and warmer conditions Wednesday and Thursday. Temperatures should recover to slightly above normal by Thursday. Increasing southwesterly flow aloft is forecast for Friday, with the first in a new series of weather systems likely pushing rain onshore Friday afternoon and night. Expect showery and cool weather on Saturday and brief drying on Sunday. Rain should return by Sunday night. A generally cool and somewhat damp weather pattern is forecast for 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 18 08:41:48 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 18 Sep 2013 08:41:48 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT WED SEP 18, 2013 BURN ADVISORY: Recommended times for agricultural burning are from 11 a.m. until 4:30 p.m.. WEATHER DISCUSSION: Northwesterly flow aloft is in place behind yesterday's disturbance, which is east of Oregon today. Mostly cloudy skies cover the Silverton Hills this morning, but a clearing trend is expected through the late morning. Afternoon mixing heights are likely to rise to above 5000 feet, with temperatures just below seasonal average and partly cloudy skies. Weak winds are expected. TODAY'S FORECAST: Partly cloudy. Salem's high temperature today will be near 72 degrees (average is 75). Relative humidity: Drops below 60% 1 p.m. and to near 50% by 5 p.m. Surface winds: Light and variable this morning; becoming N 5 mph this afternoon. Transport winds: NW 5-10 mph this morning; becoming NE 5-10 mph this afternoon. Mixing height: Rising to 4000 feet by early afternoon and to above 5000 feet by 5 p.m.. Salem's sunset tonight: 7:16 p.m. (Salem Airport data for Tuesday, Sept. 17th: High 72?F; Rainfall: Trace) (Maximum Ventilation Index expected today: 40) EXTENDED DISCUSSION: Upper ridging will dominate Thursday with surface warming to near the seasonal average and dry conditions. Increasing southwesterly flow aloft is forecast for Friday as a major trough approaches from the west, likely pushing rain onshore Friday afternoon and night. Expect rainy and cool weather on Saturday and mostly cloudy, cool conditions Sunday. A new strong trough is forecast to move onshore from the west Sunday night, and for early next week more rain and even cooler temperatures appear likely at this point. 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 19 08:53:19 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 19 Sep 2013 08:53:19 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT THU SEP 19, 2013 BURN ADVISORY: Recommended times for agricultural burning are from 1:00 p.m. until 5:00 p.m.. WEATHER DISCUSSION: The upper ridge axis is east of the area today as new strong troughing is developing off the Pacific coast. The trough's weather will hold off for a day and warm, dry conditions will dominate today as southerly winds develop aloft. Afternoon mixing heights are likely to rise to above 3000 feet, with high temperatures above the seasonal average and mostly sunny skies. Weak winds are expected. TODAY'S FORECAST: Mostly sunny. Salem's high temperature today will be around 80 (average is 75). Relative humidity: Drops near 50% by noon and to near 30% by 5 p.m. Surface winds: Light and variable this morning; becoming S 5-10 mph by mid-afternoon. Transport winds: SSE 5 mph by late morning; becoming S 5-10 mph this afternoon. Mixing height: Rising to 3500 feet by late afternoon. Salem's sunset tonight: 7:14 p.m. (Salem Airport data for Wed., Sept. 18th: High 74?F; rainfall 0) (Maximum Ventilation Index expected today: 25) EXTENDED DISCUSSION: Increasing southerly flow aloft is forecast for Friday as the major trough approaches from the west, pushing a cold front and rain showers onshore into the area Friday afternoon and evening. Expect rainy and cool weather on Saturday, and then mostly cloudy, cool conditions much of Sunday between frontal systems. A new strong trough is forecast to move onshore from the west late on Sunday, bringing another round of precipitation. For early next week more rain and even cooler temperatures appear likely for the area at this point. 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Fri Sep 20 08:41:21 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 20 Sep 2013 08:41:21 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT FRI SEP 20, 2013 BURN ADVISORY: Recommended times for agricultural burning are from 11:00 a.m. until 5:00 p.m.. WEATHER DISCUSSION: The strong trough and cold front just west of us is currently moving onshore, bringing extensive middle and upper-level clouds with it and rain off the coast this morning. Deep south-southwesterly flow is developing ahead of the trough. Rain showers are expected to develop this afternoon over the Silverton Hills with breezy south winds. Afternoon mixing heights are likely to rise to moderately high levels as the cold air aloft moves in. High temperatures will be lower today as the trough approaches and frontal passage occurs later today. TODAY'S FORECAST: Mostly cloudy and cooler with showers likely by mid-afternoon. Salem's high temperature today will be in the low 70s (average is 75). Relative humidity: Drops near 60% by noon and then increasing as showers move in this afternoon. Surface winds: Becoming SSW 5-10 mph by late morning and 5-15 mph for the afternoon. Transport winds: SSW 15 mph by late morning and strengthening this afternoon. Mixing height: Rising to 3-4000 feet by mid-afternoon. Salem's sunset tonight: 7:13 p.m. (Salem Airport data for Thurs., Sept. 19th: High 80?F; rainfall 0) (Maximum Ventilation Index expected today: 65) EXTENDED DISCUSSION: Expect cloudy, rainy and cool weather on Saturday through Monday as strong onshore flow continues and the upper trough is reinforced late in the weekend into early next week. At this point looks like Tuesday will be cool with a continued chance of rain; precipitation chances are expected to begin to diminish by mid-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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Mon Sep 23 08:42:50 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 23 Sep 2013 08:42:50 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT MON SEP 23, 2013 BURN ADVISORY: Recommended times for agricultural burning are from 8:00 a.m. until 5:00 p.m. WEATHER DISCUSSION: A strong and moist WSW flow aloft will continue over Oregon today. Satellite imagery this morning shows cloudy skies, associated with a weak cold front, covering virtually all of western Oregon. Radar shows scattered showers across the Willamette Valley, with more showers moving onto the north coast. Conditions will be too damp for burning today, with high relative humidity and continued shower activity. An additional tenth of an inch of rain may fall in the Silverton Hills. TODAY'S FORECAST: Unseasonably cool with occasional showers. Salem's high temperature today will be near 62 degrees (normal is 75). Relative humidity: Remaining above 70% throughout the day. Surface winds: S 10 mph this morning; SW 10-15 mph this afternoon. Transport winds: SW 20 mph. Mixing height: Rising to 3000 feet this afternoon. Salem's sunset tonight: 7:07 p.m. (Salem Airport data for Sunday, Sept. 22nd: High 62?F; Rainfall: .22") (Maximum Ventilation Index expected today: 60) EXTENDED DISCUSSION: In the wake of today's weak cold front, an unseasonably cool upper-level trough is forecast to move over the Pacific Northwest Tuesday and Wednesday. That will maintain showery and quite cool conditions with a chance of thundershowers. Local quarter-inch rainfall amounts are possible. A drier northwesterly flow aloft will clear skies Thursday and Friday, with temperatures progressively recovering to near average. The flow aloft will turn southwesterly over the weekend, with a slow-moving cold front slated to bring more wet weather to the region 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Tue Sep 24 08:41:20 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 24 Sep 2013 08:41:20 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT TUE SEP 24, 2013 BURN ADVISORY: Recommended times for agricultural burning are from now until 5:00 p.m. WEATHER DISCUSSION: In the wake of Monday's cold front, a strong early-autumn upper-level trough is forecast to move over the Pacific Northwest Today. That will maintain showery and quite cool conditions with a chance of thundershowers. Satellite imagery shows clouds blanketing western Oregon this morning with radar and surface reports indicating numerous showers across the Willamette Valley. Surface winds are light this morning, but onshore flow is expected to increase later today. Daytime heating will combine with cold air aloft to destabilize the air mass this afternoon...leading to some thundershower development over western Oregon. Conditions will be too damp for burning again today, with high relative humidity and continued shower activity. Additional rainfall totals could exceed one-quarter of an inch in the Silverton Hills. TODAY'S FORECAST: Showers and continued unseasonably cool. Chance of thundershowers. Salem's high temperature today will be near 62 degrees (average is 74). Relative humidity: Remaining above 70% throughout the day. Surface winds: W 2-5 mph this morning; SW 5-10 mph this afternoon. Transport winds: SW 10-15 mph. Mixing height: Rising to above 5000 feet this afternoon. Salem's sunset tonight: 7:05 p.m. (Salem Airport data for Monday, Sept. 23rd: High 64?F; Rainfall: .36") (Maximum Ventilation Index expected today: 75+) EXTENDED DISCUSSION: A strong upper-level trough will maintain cool and showery conditions across western Oregon on Wednesday, but the strongest showers will move south of the Silverton Hills. Rainfall totals should be around one-tenth of an inch. A dry and cool northerly flow aloft will clear skies on Thursday. After a chilly morning, daytime temperatures should recover to within about 5 degrees of average. A weak upper-level ridge is forecast to move over the region on Friday. Computer models are unclear as to whether it will be a strong enough to keep of weakening cold front from dragging across northern Oregon. Some clouds are likely with temperatures recovering to near average. A strengthening trough, in the Gulf of Alaska, is forecast to turn the flow aloft southwesterly over the weekend. At this point, Saturday looks dry and warmer, but a slow-moving cold front is still slated to bring some rain back to the region by Sunday afternoon. A flat upper-level ridge is forecast to keep Oregon on the southern edge of the storm track early next week, with sunny and much warmer weather possible beginning a week from Thursday. 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Wed Sep 25 08:57:43 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 25 Sep 2013 08:57:43 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_Pete.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT WED SEP 25, 2013 BURN ADVISORY: Recommended times for agricultural burning are from now until 5:00 p.m. WEATHER DISCUSSION: A strong upper-level trough will maintain cool and showery conditions across western Oregon today. The center of circulation is dropping southward just off the central Oregon coast this morning and will take the strongest shower activity into SW Oregon this afternoon. Additional rainfall totals in the Silverton Hills should be only near one-tenth of an inch, with northerly flow aloft likely bringing partial clearing to the Willamette Valley later today. Satellite imagery shows clouds blanketing most of the state this morning with radar and surface reports indicating scattered showers across the Willamette Valley. Surface winds are light southwesterly this morning but should increase and turn northwesterly this afternoon. TODAY'S FORECAST: Showers and continued unseasonably cool. Partial afternoon clearing. Salem's high temperature today will be near 61 degrees (average is 74). Relative humidity: Remaining above 60% throughout the day. Surface winds: W 5-10 mph this morning; NW 7-15 mph this afternoon. Transport winds: W 10 mph this morning; NW 10-15 mph this afternoon. Mixing height: Above 5000 feet throughout the day. Salem's sunset tonight: 7:03 p.m. (Salem Airport data for Tuesday, Sept. 24th: High 61?F; Rainfall: .40") (Maximum Ventilation Index expected today: 75) EXTENDED DISCUSSION: A dry and cool northerly flow aloft will clear skies on Thursday. After a chilly and perhaps foggy morning, daytime temperatures should only recover into the mid 60s, even with some afternoon sunshine. A weak upper-level ridge is forecast to move over the region on Friday. The southern end of a cold front is forecast to drag across Washington and northern Oregon Friday afternoon. It will likely keep skies mostly cloudy and may be strong enough to produce light rain as far south as the Silverton Hills. Temperatures will remain below average. A strengthening trough, in the Gulf of Alaska, is forecast to turn the flow aloft southwesterly over the weekend. Expect mostly cloudy skies with increasing southerly winds. Rain may extend south into the region on Saturday and is likely on Sunday. Temperatures will remain slightly below normal. A flat upper-level ridge is forecast to keep Oregon on the southern edge of the storm track through the middle of next week, with possibly warmer and drier weather late 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 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Pete Parsons ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Thu Sep 26 08:45:58 2013 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 26 Sep 2013 08:45:58 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast_doug.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 9:00 AM PDT THU SEP 26, 2013 BURN ADVISORY: Recommended times for agricultural burning are from 2:00 p.m. until 5:00 p.m. WEATHER DISCUSSION: A strong upper-level trough centered just east of the area has us in cool, deep northwesterly flow after another round of light rain showers yesterday. A few lingering light showers this morning are possible. The center of the trough is moving southeastward into the intermountain west today. Partly cloudy skies and very cool conditions are expected to continue today with some northwesterly surface winds developing by this afternoon. Very moist ground/field conditions are ongoing. TODAY'S FORECAST: Partly cloudy and continued unseasonably cool. Salem's high temperature today will be in the middle 60s (average is 73). Relative humidity: Remaining above 60% throughout the day. Surface winds: Light this morning; NW 5-15 mph this afternoon. Transport winds: NW 5 mph this morning; NW 10-15 mph during the afternoon. Mixing height: Rising to above 5000 feet by mid-afternoon. Salem's sunset tonight: 7:01 p.m. (Salem data for Wed., Sept. 25th: High 63?F, Low 46?F; Rainfall: .01") (Maximum Ventilation Index expected today: 65) EXTENDED DISCUSSION: The next in a series of strong, progressive Pacific storms will begin to impact the area on Friday afternoon with showers developing and onshore flow increasing. Prior to this onset, surface temperatures will likely get up into the upper 60s for highs. Saturday and Sunday are expected to be cool, showery days, and this is expected to continue into early next week. Significant rains are likely at times over the region from late Friday all the way through at least Monday. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 15mph. 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 and the Oregon Department of Forestry. For information contact ODA at 503-986-4701. Doug Wesley ODF Meteorologist -------------- next part -------------- An HTML attachment was scrubbed... URL: