From willamette-fcst at listsmart.osl.state.or.us Mon Oct 1 08:15:23 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 01 Oct 2012 11:15:23 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Mon, Oct 01 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Mon Oct 1 11:41:42 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 01 Oct 2012 14:41:42 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Mon, Oct 01 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Tue Oct 2 08:47:58 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 02 Oct 2012 11:47:58 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Tue, Oct 02 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Tue Oct 2 11:45:26 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 02 Oct 2012 14:45:26 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Tue, Oct 02 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Wed Oct 3 08:57:12 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 3 Oct 2012 08:57:12 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT WED OCT 3, 2012 BURN ADVISORY: ...State Fire Marshal Burn-Ban Conditions are expected this afternoon due to low relative humidity (? 30%) and increasing N to NE wind (? 15 mph). Agricultural burning is not recommended. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: Northwesterly flow aloft, around a building upper-level ridge in the Gulf of Alaska, drove a dry cold front southward across eastern Washington and eastern Oregon on Tuesday. The dry cold front extended from SE Idaho across northern Nevada this morning. In its wake, an unseasonably cold and dry Canadian air mass is settling into eastern Oregon, where many locations were well below freezing early this morning. Cool and dry air is now pouring through the Columbia Gorge, into the northern Willamette Valley, via brisk easterly winds gusting to near 30 mph in Portland. Strong NE pressure gradients will force the dry air southward across all of western Oregon today. The combination of low relative humidity and increasing NE winds should put the Willamette Valley into State Fire Marshal Burn-Ban Conditions this afternoon. Salem's sounding this morning showed NE winds from just above the surface up through 5000 feet. Warm air aloft should keep afternoon mixing heights from climbing much above 3000 feet, even with plenty of sunshine. (Salem Airport data for Tuesday, Oct. 2nd: High 71?F; Rainfall .00") TODAY'S FORECAST: Sunny. Turning Breezy. Salem's high temperature today will be near 70 degrees (normal is 70). Relative humidity: Dropping below 30% by 1 p.m. and to near 20% by 5 p.m. Surface winds: N 5-15 mph; becoming NE 12-20 mph this afternoon. Transport winds: NE 15 mph; becoming NE 15-25 mph this afternoon. Mixing height: Rising to near 3000 this afternoon. Salem's sunset tonight: 6:48 p.m. THREE-HOURLY DATA: 11 a.m. 2 p.m. 5 p.m. 8 p.m. Temperature: 56 67 70 55 Relative Humidity: 43% 24% 20% 41% Surface Wind Dir/Speed: N 8 NE 15 NE 15 NE 15 Transport Wind Dir/Speed: NE 15 NE 20 NE 25 NE 20 Mixing Height: 1000 2300 3000 1200 Ventilation Index: 15 46 75 24 EXTENDED DISCUSSION: Little change in the weather pattern is expected through Saturday, with continued sunny skies and dry offshore flow through the transport layer. Offshore flow should slacken by Sunday; possibly turning briefly onshore Monday, before turning offshore again during the middle of next week. It is uncertain whether this brief switch in wind direction will present a burning opportunity. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 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. 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.doc Type: application/msword Size: 33280 bytes Desc: Silverton Hills AM Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Wed Oct 3 11:58:00 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 3 Oct 2012 11:58:00 -0700 Subject: [willamette-fcst] Silverton Hills Midday Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT WED OCT 3, 2012 BURN ADVISORY: ...State Fire Marshal Burn-Ban Conditions are in effect due to low relative humidity (? 30%) and brisk N to NE wind (? 15 mph). Agricultural burning is not recommended. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: Northwesterly flow aloft, around a building upper-level ridge in the Gulf of Alaska, drove a dry cold front southward across eastern Washington and eastern Oregon on Tuesday. In its wake, an unseasonably cold and dry Canadian air mass is settling into eastern Oregon. Cool and dry air is pouring through the Columbia Gorge, into the northern Willamette Valley, via strong easterly winds gusting to near 40 mph in Portland. Brisk NE wind, gusting to near 30 mph, have also picked up in the central Willamette Valley. Smoke from wildfires is being transported across NW Oregon, with air quality gauges showing an increase in particulate levels late this morning. Warm air aloft should keep afternoon mixing heights from climbing much above 3000 feet, even with hazy sunshine. TODAY'S FORECAST: Sunny, hazy, and breezy. Salem's high temperature today will be near 70 degrees (normal is 70). Relative humidity: Dropping below 20% by 5 p.m. Surface winds: NE 12-20 mph this afternoon. Transport winds: NE 20-30 mph this afternoon. Mixing height: Rising to near 3000 this afternoon. Salem's sunset tonight: 6:48 p.m. THREE-HOURLY DATA: 2 p.m. 5 p.m. 8 p.m. Temperature: 67 70 55 Relative Humidity: 20% 18% 41% Surface Wind Dir/Speed: NE 15 NE 15 NE 15 Transport Wind Dir/Speed: NE 20 NE 25 NE 20 Mixing Height: 2300 3000 1200 Ventilation Index: 46 75 24 EXTENDED DISCUSSION: Little change in the weather pattern is expected through Saturday, with continued sunny skies and dry offshore flow through the transport layer. Offshore flow should slacken by Sunday; possibly turning briefly onshore Monday, before turning offshore again during the middle of next week. It is uncertain whether this brief switch in wind direction will present a burning opportunity. The upper-level ridge is forecast to maintain dry and fairly stagnant conditions through Thursday of next week. However, there are indications that the first in a series of fall storms may move onshore next 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 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. 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.doc Type: application/msword Size: 32256 bytes Desc: Silverton Hills Midday Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Oct 4 08:57:36 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 4 Oct 2012 08:57:36 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT THU OCT 4, 2012 BURN ADVISORY: ...State Fire Marshal Burn-Ban Conditions may be reached this afternoon due to the combination of low relative humidity (? 30%) and wind (? 15 mph). Agricultural burning is not recommended. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: Northwesterly flow aloft is continuing, with an unseasonably cold and dry Canadian air mass over Oregon. Most locations east of the Cascades fell below freezing this morning. Meacham, in NE Oregon, dropped into the mid teens, with Redmond, in central Oregon, dipping into the low 20s. Meanwhile, temperatures were not as cold across western Oregon, but some spots in the Willamette Valley saw the upper 30s. A surface thermal trough is trying to build northward along the southern Oregon coast, which is forcing cool and very dry air west of the Cascades, via east to northeast winds. Pressure gradients have relaxed some today, but NE winds may still be strong enough to put the Willamette Valley into State Fire Marshal Burn-Ban Conditions this afternoon. Some wildfire smoke is also getting transported across NW Oregon, making for hazy conditions. Satellite imagery shows clear skies across all of Oregon this morning, with the exception of low clouds and fog along the southern coast. The morning sounding over Salem showed a few degrees of warming aloft, compared to yesterday (from just above the surface through 6000 feet). Warm air aloft should keep mixing heights to below 3000 feet this afternoon. (Salem Airport data for Wednesday, Oct. 3rd: High 74?F; Rainfall .00") TODAY'S FORECAST: Sunny, hazy, and breezy. Salem's high temperature today will be near 75 degrees (normal is 70). Relative humidity: Dropping below 30% by 11 a.m. and below 20% by 2 p.m. Surface winds: NE 5-10 mph; increasing to near 15 mph this afternoon. Transport winds: NE 15-20 mph; increasing to 20-25 mph this afternoon. Mixing height: Rising to near 2800 feet this afternoon. Salem's sunset tonight: 6:46 p.m. THREE-HOURLY DATA: 11 a.m. 2 p.m. 5 p.m. 8 p.m. Temperature: 65 73 73 61 Relative Humidity: 26% 17% 19% 30% Surface Wind Dir/Speed: NE 10 NE 15 NE 15 NE 12 Transport Wind Dir/Speed: NE 17 NE 23 NE 25 NE 20 Mixing Height: 1800 2800 2800 1200 Ventilation Index: 31 64 70 24 EXTENDED DISCUSSION: Little change in the weather pattern is expected through Saturday, with continued sunny skies and dry offshore flow through the transport layer. Offshore flow should weaken early next week, but there are no indications that this will create any burning opportunities. The upper-level ridge is forecast to maintain dry and stagnant weather through at least next Thursday. A very weak weather system may put a dent in the strong ridge over the region next Friday; possibly turning transport winds onshore enough to create a burning opportunity. That may also be the beginning of a pattern change to a more fall-like regime. 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. 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.doc Type: application/msword Size: 33792 bytes Desc: Silverton Hills AM Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Oct 4 11:38:48 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 4 Oct 2012 11:38:48 -0700 Subject: [willamette-fcst] Silverton Hills Midday Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:40 AM PDT THU OCT 4, 2012 BURN ADVISORY: ...State Fire Marshal Burn-Ban Conditions are likely this afternoon due to the combination of low relative humidity (? 30%) and wind (? 15 mph). Agricultural burning is not recommended. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: A strong upper-level ridge of high pressure, centered in the Gulf of Alaska, is continuing the dry and stable northwesterly flow aloft over Oregon. A surface thermal trough is building northward along the southern Oregon coast. That is forcing very dry air, from eastern Oregon, through the Columbia Gorge and Cascades passes into the Willamette Valley. Relative humidity values in the Willamette Valley have already dropped to near or below 30%, and wind speeds are approaching 15 mph. State Fire Marshal Burn-Ban Conditions are likely this afternoon. Satellite imagery shows clear skies across all of Oregon this morning, with the exception of low clouds and fog along the southern coast. However, wildfire smoke is making for hazy conditions across most of the state, including the Willamette Valley. The air aloft has warmed slightly since yesterday, so mixing heights should stay below 3000 feet this afternoon. TODAY'S FORECAST: Sunny, hazy, and breezy. Salem's high temperature today will be near 75 degrees (normal is 70). Relative humidity: Dropping to near 20% this afternoon. Surface winds: NE 10-18 mph. Transport winds: NE 20-25 mph. Mixing height: Rising to near 2800 feet this afternoon. Salem's sunset tonight: 6:46 p.m. THREE-HOURLY DATA: 2 p.m. 5 p.m. 8 p.m. Temperature: 73 73 61 Relative Humidity: 20% 19% 30% Surface Wind Dir/Speed: NE 15 NE 15 NE 12 Transport Wind Dir/Speed: NE 23 NE 25 NE 20 Mixing Height: 2800 2800 1200 Ventilation Index: 64 70 24 EXTENDED DISCUSSION: Little change in the sunny and stable conditions is expected through most of next week. Offshore flow should weaken by Monday, but there are no indications that this will create any burning opportunities. The upper-level ridge is forecast to weaken by next Friday, with a mostly dry cold front possibly turning transport winds onshore and creating a burning opportunity. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 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. 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.doc Type: application/msword Size: 32256 bytes Desc: Silverton Hills Midday Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Oct 5 08:49:55 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 5 Oct 2012 08:49:55 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:50 AM PDT FRI OCT 5, 2012 BURN ADVISORY: ...State Fire Marshal Burn-Ban Conditions may be reached this afternoon due to the combination of low relative humidity (? 30%) and wind (? 15 mph). Agricultural burning is not recommended. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: A strong upper-level ridge of high pressure, centered in the Gulf of Alaska, is producing a dry and stable northerly flow aloft over Oregon. A surface thermal trough is building northward along the Oregon coast. That is continuing to draw very dry air into the Willamette Valley through the Columbia Gorge and the Cascades passes. Pressure gradients have relaxed somewhat, but State Fire Marshal Burn-Ban Conditions are still possible this afternoon, as wind speeds approach 15 mph. Satellite imagery shows clear skies across the interior of Oregon. However, low clouds and fog have moved northward along the coast to about Tillamook. Wildfire smoke is continuing to make for hazy conditions across most of the state, including the Willamette Valley. Slightly cooler air aloft will allow mixing heights to climb to about 4000 feet this afternoon. (Salem Airport data for Thursday, Oct. 4th: High 76?F; Rainfall .00") TODAY'S FORECAST: Sunny but a little hazy. Not as breezy. Salem's high temperature today will be near 75 degrees (normal is 69). Relative humidity: Dropping below 30% by 11 a.m. and below 20% by 2 p.m. Surface winds: NE 5-10 mph; increasing to 10-15 mph this afternoon. Transport winds: NE 10 mph; increasing to 12-20 mph this afternoon. Mixing height: Rising to near 4000 feet this afternoon. Salem's sunset tonight: 6:44 p.m. THREE-HOURLY DATA: 11 a.m. 2 p.m. 5 p.m. 8 p.m. Temperature: 63 73 73 60 Relative Humidity: 27% 19% 17% 29% Surface Wind Dir/Speed: NE 6 NE 12 NE 12 NE 7 Transport Wind Dir/Speed: NE 10 NE 16 NE 18 NE 10 Mixing Height: 1200 4000 4000 1200 Ventilation Index: 12 64 72 12 EXTENDED DISCUSSION: Sunny and stable conditions are expected to persist through Wednesday of next week, with lighter, mostly northeasterly, winds. Some smoke dispersion models are showing a significant decrease in air quality for the Willamette Valley over the weekend, but that will depend largely on the amount of smoke produced by area wildfires. The upper-level ridge is forecast to finally push east of the state next Thursday, with the flow aloft becoming southwesterly. A cold front may create a burning opportunity Thursday afternoon or Friday. The timing of the system is crucial, because it may bring enough rain to dampen fields. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 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. 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.doc Type: application/msword Size: 33280 bytes Desc: Silverton Hills AM Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Oct 5 11:56:41 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 5 Oct 2012 11:56:41 -0700 Subject: [willamette-fcst] Silverton Hills Midday Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT FRI OCT 5, 2012 BURN ADVISORY: ...State Fire Marshal Burn-Ban Conditions have been met in the northern Willamette Valley, due to the combination of low relative humidity (? 30%) and wind (? 15 mph), and may spread south this afternoon. Agricultural burning is not recommended. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: A strong upper-level ridge of high pressure, centered in the Gulf of Alaska, is producing a dry and stable northerly flow aloft over Oregon. A surface thermal trough is building northward along the Oregon coast. That is continuing to draw very dry air into the Willamette Valley through the Columbia Gorge and the Cascades passes. East winds were gusting to over 20 mph in the northern Willamette Valley this morning, as far south as Aurora and McMinnville. Brisk east winds and low humidity levels have already put north valley locations, from about Woodburn north, into State Fire Marshal Burn-Ban Conditions. Increasing north to northeast winds may extend the burn-ban conditions into the central and southern valley again this afternoon. Satellite imagery shows clear skies across most of Oregon. However, low clouds and fog have moved from the southern Oregon coast into portions of the southwest interior. Patchy low clouds also extend northward along the coast to about Tillamook. Wildfire smoke is continuing to make for hazy conditions across most of the state, including the Willamette Valley. TODAY'S FORECAST: Sunny but hazy. Increasingly breezy, but not as windy as yesterday. Salem's high temperature today will be near 75 degrees (normal is 69). Relative humidity: Dropping below 20% by 2 p.m. Surface winds: NE 5-10 mph; increasing to 10-15 mph this afternoon. Transport winds: NE 10 mph; increasing to 12-20 mph this afternoon. Mixing height: Rising to near 4000 feet this afternoon. Salem's sunset tonight: 6:44 p.m. THREE-HOURLY DATA: 2 p.m. 5 p.m. 8 p.m. Temperature: 73 73 60 Relative Humidity: 19% 17% 29% Surface Wind Dir/Speed: NE 12 NE 12 NE 7 Transport Wind Dir/Speed: NE 16 NE 18 NE 10 Mixing Height: 4000 4000 1200 Ventilation Index: 64 72 12 EXTENDED DISCUSSION: Sunny and stable conditions are expected to persist through Wednesday of next week, with lighter, mostly northeasterly, winds. Some air quality models are showing a significant increase in smoke and haze for the Willamette Valley, especially during the overnight periods, but that will depend largely on the amount of new smoke produced by area wildfires. The upper-level ridge is forecast to finally push east of the state late next week, which would open the door for fall storms to begin coming onshore. Typically, the initial weather system is fairly weak, and the latest computer guidance is showing it splitting as it moves onshore late Friday. It is unlikely to produce much rainfall but could create an opportunity to burn any remaining fields on Friday. Much stronger systems are forecast to quickly follow, bringing more significant rain to the valley. The National Weather Service's digital forecast is available at: http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text Notes: 1. Mixing height, as used here, is the lowest height at which the potential temperature exceeds the potential temperature at the surface. As a practical matter it is the approximate height to which a smoke plume will rise assuming good ignition, dry fuels, and winds less than about 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. 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.doc Type: application/msword Size: 33280 bytes Desc: Silverton Hills Midday Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Mon Oct 8 08:21:29 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 08 Oct 2012 11:21:29 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Mon, Oct 08 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Mon Oct 8 11:53:18 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Mon, 08 Oct 2012 14:53:18 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Mon, Oct 08 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Tue Oct 9 08:33:40 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 09 Oct 2012 11:33:40 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Tue, Oct 09 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Tue Oct 9 11:52:03 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 09 Oct 2012 14:52:03 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Tue, Oct 09 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Tue Oct 9 11:53:36 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Tue, 09 Oct 2012 14:53:36 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Tue, Oct 09 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Wed Oct 10 08:33:29 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 10 Oct 2012 11:33:29 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Wed, Oct 10 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Wed Oct 10 11:34:16 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Wed, 10 Oct 2012 14:34:16 -0400 Subject: [willamette-fcst] Field Burning Forecast for Silverton Hills - Wed, Oct 10 2012 Message-ID: An HTML attachment was scrubbed... URL: -------------- next part -------------- An HTML attachment was scrubbed... URL: From willamette-fcst at listsmart.osl.state.or.us Thu Oct 11 08:57:08 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 11 Oct 2012 08:57:08 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT THU OCT 11, 2012 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: An upper-level ridge remains over Oregon this morning. At the surface, a broad thermal trough covers most of western Oregon with weak pressure gradients and calm winds across the Willamette Valley. A blanket of fog formed across the Willamette Valley overnight, and visibilities this morning are locally less than one-quarter of a mile. Air quality monitoring equipment is also continuing to show some haze across the valley. The Salem sounding and local pilot reports indicate that the top of the fog layer is no higher than 2000 feet, so it should burn off by mid-afternoon. Much like yesterday, mixing heights will likely top out between 2000 and 2500 feet, once surface temperatures are able to climb into the upper 60s. Transport winds are forecast to remain light today, but may turn lightly onshore late this afternoon, as the upper-level ridge begins to weaken and shift to the east. There may be a late-afternoon burning opportunity today, very similar to yesterday, if the valley can get enough sunshine. Transport winds will likely remain light, but an approaching cold front will bring increasing onshore flow tonight, which will aid in smoke evacuation. This will likely be the last burning opportunity of the season (see extended discussion). (Salem Airport data for Wednesday, Oct. 10th: High 72?F; Rainfall .00") TODAY'S FORECAST: Morning fog; becoming sunny but a little hazy in the afternoon. Salem's high temperature today will be near 70 degrees (normal is 66). Relative humidity: Dropping to near 50% by 2 p.m. and to 45% by 5 p.m. Surface winds: Light and variable. Transport winds: Light and variable. Mixing height: Rising to near 2500 feet this afternoon. Salem's sunset tonight: 6:33 p.m. THREE-HOURLY DATA: 11 a.m. 2 p.m. 5 p.m. 8 p.m. Temperature: 53 65 69 57 Relative Humidity: 77% 50% 44% 67% Surface Wind Dir/Speed: Calm Var 3 Var 3 SW 3 Transport Wind Dir/Speed: SE 3 NW 3 NW 3 SW 4 Mixing Height: 1200 2200 2500 1000 Ventilation Index: 4 7 8 4 EXTENDED DISCUSSION: The upper-level ridge that has been over the Pacific Northwest since July is finally going to give way to a strengthening westerly jet stream on Friday. The first in a series of progressively stronger weather systems will come onshore Friday morning. The latest computer guidance is showing rain moving into the northern Willamette Valley around midday, so a burning opportunity ahead of this system appears unlikely. Rain will likely spread southward across the valley Friday afternoon. Look for mostly cloudy skies over the weekend with a chance of light rain at times, as the main storm track takes aim at Washington. The jet stream is forecast to sag southward across Oregon late Sunday and Monday, with significant rain likely. 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. 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.doc Type: application/msword Size: 32256 bytes Desc: Silverton Hills AM Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Thu Oct 11 11:56:07 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Thu, 11 Oct 2012 11:56:07 -0700 Subject: [willamette-fcst] Silverton Hills Midday Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT THU OCT 11, 2012 BURN ADVISORY: Agricultural burning is not recommended. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: Fog continued to blanket much of the Willamette Valley late this morning, but visibilities were beginning to improve. Some break-up of the fog had begun, especially in the south valley. Late-morning temperatures were only in the mid to upper 40s in foggy areas, but partly sunny skies had already boosted Eugene into the low 50s. The fog layer should continue to break up, with mostly sunny skies likely by about 2 p.m. in the Silverton Hills. There may be a late-afternoon burning opportunity today, very similar to yesterday, if the valley can get enough sunshine. The air aloft remains quite warm, so surface temperatures will need to reach the low 60s to achieve 2000-foot mixing heights. Pressure gradients are very weakly onshore with light and variable winds across the valley. Transport winds are forecast to remain lightly onshore this afternoon. Pibals are scheduled to begin either at 1:00 p.m. or when the fog lifts. An approaching cold front will bring increasing onshore flow tonight, which will aid in smoke evacuation. However, it will also usher in a very moist air mass, likely ending the 2012 field-burning season. TODAY'S FORECAST: Fog giving way to mostly sunny but hazy skies this afternoon. Salem's high temperature today will be near 67 degrees (normal is 66). Relative humidity: Dropping to near 50% by 5 p.m. Surface winds: Light and variable. Transport winds: Light and variable; becoming SW to NW 3-5 mph late. Mixing height: Rising to near 2500 feet by late this afternoon. Salem's sunset tonight: 6:33 p.m. THREE-HOURLY DATA: 2 p.m. 5 p.m. 8 p.m. Temperature: 63 66 57 Relative Humidity: 54% 49% 67% Surface Wind Dir/Speed: Var 3 Var 3 SW 3 Transport Wind Dir/Speed: NW 3 SW 3 SW 4 Mixing Height: 2200 2500 1000 Ventilation Index: 7 8 4 EXTENDED DISCUSSION: The upper-level ridge that has been over the Pacific Northwest since July will give way to a strengthening westerly jet stream on Friday. The first in a series of progressively stronger weather systems will come onshore Friday morning. The latest computer guidance is showing rain moving into the northern Willamette Valley in the afternoon. The air mass ahead of the front will likely be too moist to allow for burning. Look for mostly cloudy skies Saturday and early Sunday with a chance of light rain at times. A couple of quite potent storms are forecast to bring soaking rains to western Oregon Sunday afternoon through 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 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. 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.doc Type: application/msword Size: 32256 bytes Desc: Silverton Hills Midday Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Oct 12 08:52:44 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 12 Oct 2012 08:52:44 -0700 Subject: [willamette-fcst] Silverton Hills AM Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 8:55 AM PDT FRI OCT 12, 2012 BURN ADVISORY: Recommended burn times for agricultural burning are 8:00 a.m. until 4:30 p.m. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: The upper-level ridge that has been over the Pacific Northwest since July has flattened in response to a strengthening westerly jet stream. The first in a series of progressively stronger weather systems is moving onshore this morning. Radar and surface reports indicate that areas of light rain have already advanced from the northern and central coast into the northern Willamette Valley. What was left of a thermal trough has progressed into eastern Oregon, which has turned transport winds strongly onshore across northwestern Oregon. That has helped to clear the haze from the valley this morning, with air quality instruments mostly returning to baseline readings. Surface winds have turned southerly at 5-10 mph in the valley and should increase slightly later today. The air mass will likely remain too moist for burning today, with areas of light rain increasing in coverage this afternoon. (Salem Airport data for Thursday, Oct. 11th: High 69?F; Rainfall .00") TODAY'S FORECAST: Cloudy and much cooler with light rain at times. Salem's high temperature today will be near 56 degrees (normal is 66). Relative humidity: Remaining above 75% all day. Surface winds: S 5-15 mph. Transport winds: SW 15 mph; becoming SW 20-25 mph this afternoon. Mixing height: Rising to near 3500 feet this afternoon. Salem's sunset tonight: 6:31 p.m. THREE-HOURLY DATA: 11 a.m. 2 p.m. 5 p.m. 8 p.m. Temperature: 52 55 56 53 Relative Humidity: 83% 77% 80% 89% Surface Wind Dir/Speed: S 7 S 10 S 10 S 7 Transport Wind Dir/Speed: SW 15 SW 20 SW 22 SW 25 Mixing Height: 2800 3000 3500 3000 Ventilation Index: 42 60 77 75 EXTENDED DISCUSSION: Continued westerly flow aloft will maintain mostly cloudy skies Saturday and Sunday with a chance of light rain at times. Valley temperatures should warm back into the 60s, as the main storm track migrates northward, to over Washington. The jet stream will drop south again late Sunday, with a couple of potent storms forecast to bring soaking rains to western Oregon Sunday night and Monday. That should effectively end field-burning for the season. 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. 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.doc Type: application/msword Size: 31744 bytes Desc: Silverton Hills AM Forecast.doc URL: From willamette-fcst at listsmart.osl.state.or.us Fri Oct 12 11:56:22 2012 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Field Burning Forecast) Date: Fri, 12 Oct 2012 11:56:22 -0700 Subject: [willamette-fcst] Silverton Hills Midday Forecast.doc Message-ID: SILVERTON HILLS FIELD BURNING FORECAST OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE 11:55 AM PDT FRI OCT 12, 2012 ...Final Forecast for the 2012 Season... BURN ADVISORY: Recommended burn times for agricultural burning are now until 4:30 p.m. Prep burning is not allowed. Propane flaming is not allowed. WEATHER DISCUSSION: The upper-level ridge that has been over the Pacific Northwest since July has flattened in response to a strengthening westerly jet stream. The first in a series of progressively stronger weather systems pushed areas of light rain onto the northern and central coast this morning, with rain progressing inland across most of the Willamette Valley by midday. Hillsboro and McMinnville have both recorded close to one-quarter of an inch, with much lighter totals in Corvallis and Salem. Late-morning satellite imagery showed clouds covering virtually all of Washington and western Oregon. Radar showed bands of light rain extending southward to about Eugene with some light rain pushing eastward into the northern Cascades. Bands of light rain should continue to rotate onshore today and tonight, with another tenth to one-quarter of an inch of rain possible. Light southerly winds have helped to improve air quality across the Willamette Valley. TODAY'S FORECAST: Light rain at times and much cooler. Salem's high temperature today will be near 56 degrees (normal is 66). Relative humidity: Remaining above 75% all day. Surface winds: S 5-15 mph. Transport winds: SW 15 mph; becoming SW 20-25 mph this afternoon. Mixing height: Rising to near 3500 feet this afternoon. Salem's sunset tonight: 6:31 p.m. THREE-HOURLY DATA: 2 p.m. 5 p.m. 8 p.m. Temperature: 55 56 53 Relative Humidity: 77% 80% 89% Surface Wind Dir/Speed: S 10 S 10 S 7 Transport Wind Dir/Speed: SW 20 SW 22 SW 25 Mixing Height: 3000 3500 3000 Ventilation Index: 60 77 75 EXTENDED DISCUSSION: The rain should taper off of Saturday and the first half of Sunday, as the jet stream pushes north to over Washington. Valley temperatures should warm back into the 60s. Sunday will likely be the last chance to burn any remaining fields, if they can dry out enough. The jet stream will drop south again late Sunday, with a couple of potent storms forecast to bring soaking rains to western Oregon Sunday night and Monday. That should effectively end field-burning for the season. 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. 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.doc Type: application/msword Size: 31744 bytes Desc: Silverton Hills Midday Forecast.doc URL: