From willamette-fcst at listsmart.osl.state.or.us Tue Nov 4 09:03:48 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Tue, 04 Nov 2008 11:03:48 -0600 Subject: [willamette-fcst] Forecast - Tuesday, November 4th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Tuesday, November 4th, 2008 at 9:00am. Burn Advisory: Agricultural burning is allowed. Suggested burn times are from now until 3:00pm. Straw stack burning is allowed from now until 3:00pm. Weather Discussion: A very moist Pacific storm system moved onto the southern Oregon Coastline Monday evening and northeastward across the state overnight. It dropped about one inch of rain across most of western Oregon and generally one-tenth to one-quarter of an inch across central and eastern Oregon. The ODA surface analysuis showed the low pressure system had moved into extreme southeastern Washington by mid-morning with the associated cold front pushing through central Idaho. Satellite imagery showed cloudy skies over most of Washington and east of the Cascades in Oregon. Steady precipitation was still falling across northeastern Oregon with snow being reported at Meacham (3726 feet) along I84 in the northeastern mountains. In the wake of the cold front, some breaks in the cloud cover were showing up over western Oregon, along with numerous showers. The air aloft is quite cold with the freezing levels over Salem and Medford measured at just 4400 feet and 4300 feet respectively early this morning. There was even a report of snow and hail showers this morning just south of Pleasant Valley (about 6 miles south of Tillamook). A cold upper-level trough will maintain considerable shower activity across the region today with even a slight chance of a thundershower and small hail. High temperatures will struggle to reach the low 50s with gusty southwest winds near showers. The snow level will drop to 3000 feet today with 4-8 inches of snow expected over the Cascade passes. Government Camp, Santiam Pass, and Willamette Pass had picked up several inches of snow, by mid-morning, with temperatures near 30 degrees. Even Siskiyou Summit, in southern Oregon, had picked up an inch of snow. Surface Winds: SW 10 this morning, SW 10 G20 this afternoon. Transport Winds: WSW 17 this morning, W 18 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 4000 feet. Ventilation index 72. High Temperature: Salem\'s high temperature today will be near 51. Humidities: Minimum relative humidity will be near 66%. Sunrise/Sunset: Salem sunset tonight: 4:56pm; sunrise tomorrow: 6:57am. Extended Outlook: The upper-level trough is forecast to push east of the by Wednesday mornign with the flow aloft turning northwesterly and beginning to dry out. A strong warm front will bring steady rain back to western Oregon Wednesday afternoon, and push the snow level back above the Cascade passes. The rain should taper off Thursday and Friday, as the warm front moves north, into southern British Columbia, forcing mild air back over Oregon. Another Pacific storm system is forecast to bring more rain to the region Saturday, but snow levels should remain generally above the Cascades passes. The next system is slated to come onshore Sunday evening and could bring some gusty south winds to the coastal strip. Yet another system may come onshore Tuesday, as it appears the rainly season has arrived. Tomorrow (05 Nov): Rain Developing. Snow Level 3000 Feet...Rising to 6000 Feet Late. 38/50 Thu (06 Nov): Cloudy. Chance of Light Rain. 44/59 Fri (07 Nov): Mostly Cloudy. Chance of Light Rain..Mainly North. 46/60 Sat (08 Nov): Rain Likely...Turning to Showers by Afternoon. 46/55 Sun (09 Nov): Increasing Rain and Wind Late. 42/54 Mon (10 Nov): Mostly Cloudy with Decreasing Showers. Snow Level Near 4000 Feet. 42/53 Tue (11 Nov): Rain Likely...Turning to Showers. 43/54 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Thu Nov 6 09:03:56 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Thu, 06 Nov 2008 11:03:56 -0600 Subject: [willamette-fcst] Forecast - Thursday, November 6th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Thursday, November 6th, 2008 at 9:00am. Burn Advisory: Agricultural burning is allowed. Suggested burn times are from now until 3:00pm. Straw stack burning is allowed from now until 3:00pm. Weather Discussion: A strong warm front brought rainy and cool conditions to Western Oregon Wednesday with afternoon temperatures mostly in the upper 40s across the Willamette Valley. The warm front had moved into the north valley, by this morning, with brisk southerly winds warming the central and southern Willamette Valley into the mid 50s. Steady light rain was still falling in the greater Portland area but had tapered off south of Aurora. 24-hour Rainfall totals, ending at 4 am this morning, generally ranged from one-third to two-thirds of an inch across the Willamette Valley. The Salem sounding this morning showed considerable warming aloft since Wednesday, in response to the warm front. The freezing level had jumped from 4500 feet Wednesday morning to 9300 feet this morning. Snow changed to rain overnight in the Cascade passes and was tapering off this morning. The ODA surface analysis showed strong southerly pressure gradients, in the wake of the warm front, along the coast...extending into the Willamette Valley. South winds were gusting to near 40 mph along the northern and central coast and locally over 20 mph in the Willlamette Valley. The warm front, and associated steady rain, will continue to lift northward today and tonight...maintaining the steady rainfall across western Washington. Skies should stay mostly cloudy across the Willamette Valley, but continued brisk southerly winds will likely lift afternoon temperatures into the low 60s. The warmer surface temperatures and southerly winds will make for good ventilation conditions today. There is still a chance of a little rain at times across western Oregon, but additional amounts should be less than one-tenth of an inch. Continued mild southerly winds will hold overnight temperatures in the 50s. Surface Winds: S 10-20 this morning, S 10-20 this afternoon. Transport Winds: SSW 22 this morning, SSW 25 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 2500 feet. Ventilation index 63. High Temperature: Salem\'s high temperature today will be near 62. Humidities: Minimum relative humidity will be near 67%. Sunrise/Sunset: Salem sunset tonight: 4:53pm; sunrise tomorrow: 6:59am. Extended Outlook: The rain should stay mainly north of Oregon Friday, with steady warm-frontal rain continuing across western Washington. Mild southerly winds will likely push afternoon temperatures into the low 60s again. Another Pacific storm system is forecast to bring more rain to the region Saturday, but snow levels should remain above the Cascades passes until the cold front pushes east of the region Saturday night. A cool upper-level trough will continue to bring showers to the region Sunday with the snow level around 4000 feet. The next system will likely bring back steady rain on Monday with the snow level lifting to around 5000 feet. A stronger system is forecast to bring more rain Tuesday with the snow level rising a touch more. A warm front will continue the rain Wednesday with rising snow levels. Mild southerly winds may move into the valley by Thursday, which could push temperatures back into the low 60s. Tomorrow (07 Nov): Mostly Cloudy and Mild. Chance of Light Rain..Mainly North. 52/62 Sat (08 Nov): Rain Likely...Turning to Showers by Evening. 49/55 Sun (09 Nov): Showers. Snow Level 4000 Feet. 42/52 Mon (10 Nov): Rain Likely. Snow Level Near 5000 Feet. 40/54 Tue (11 Nov): Rain Likely. Snow Level Near 5500 Feet. 43/54 Wed (12 Nov): Rain Likely. Snow Level Rising to Near 7000 Feet. 43/55 Thu (13 Nov): Mostly Cloudy and Mild. Chance of Light Rain. 49/60 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Fri Nov 7 09:04:29 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Fri, 07 Nov 2008 11:04:29 -0600 Subject: [willamette-fcst] Forecast - Friday, November 7th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Friday, November 7th, 2008 at 9:00am. Burn Advisory: Agricultural burning is allowed. Suggested burn times are from now until 3:00pm. Straw stack burning is allowed from now until 3:00pm. Weather Discussion: A strong warm stalled over westner Washington Thursday with localy heavy rain continuing to fall over northwestern Washington this morning. Rainfall amounts in the past 24 hours have been on the order of 3-5 inches across northwest Washington, from about Olympia northward. Locally heavy rain was still falling this morning in the Seatle area. Meanwhile, with the warm front north of Oregon, mild southerly winds forced Willamette Valley temperatures into the low 60s Thursday afternoon with generally dry conditions. Cloudy skies and southerly winds made for a mild night with temperatures staying in the mid to upper 50s. The morning ODA surface analysis showed the warm front stretching from the northern Washington Coast to near Seattle with southerly gradients across northwestern Oregon. South winds were continuing to blow at about 10-25 mph along the northern and central Oregon Coast and around 10 mph in the Willamette Valley. Satellite imagery showed cloudy skies extending from northwestern Washington back to a cold front, about 300 miles offshore. Clouds were increasing across northwestern Oregon, in association with the approaching cold front. Doppler radar showed a few showers coming onshore and moving across northwest Oregon with areas of light rain being reported along the coast. It was extremely mild at mid-morning with western Oregon temperatures ranging from 54 degrees in Eugene to 60 in Portland. The Salem sounding this morning was almost identical to Thursday morning below 6000 feet, with significant warming above 6000 feet. The freezing level had jumped to an unseasonably high 11,600 feet. Transport winds were still south-southwesterly but not quite as strong as on Thursday. Western Oregon should remain in the \\\"warm sector\\\" of this storm system today with continued southerly wind and mild temperaturs. There will be some scattered light showers, but rainfall amounts will be mimimal. High temperatures will, once again, climb into the low 60s. Surface Winds: S 10 this morning, S 10 this afternoon. Transport Winds: SSW 18 this morning, SSW 20 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 2000 feet. Ventilation index 40. High Temperature: Salem\'s high temperature today will be near 62. Humidities: Minimum relative humidity will be near 75%. Sunrise/Sunset: Salem sunset tonight: 4:52pm; sunrise tomorrow: 7:01am. Extended Outlook: A Pacific cold front is forecast to bring more rain to the region tonight and Saturday, but snow levels should remain above the Cascades passes until the cold front pushes east of the region Saturday evening. A cool upper-level trough will bring showers to the region Sunday and Monday, with the snow level around 4000 feet. Another system is forecast to bring more rain Tuesday with rising snow levels. A warm front will likely be strong enough to continue the rain Wednesday, with snow levels rising to well above pass levels. The cold front is forecast to push through Wednesday night and lower snow levels to near the passes Thursday. We may get a break from the rain next Friday, with another system forecast to come onshore Friday night. Tomorrow (08 Nov): Rain Likely...Turning to Showers by Evening. 52/57 Sun (09 Nov): Showers. Snow Level 4000 Feet. 42/52 Mon (10 Nov): Decreasing Showers. Snow Level Near 4500 Feet. 38/52 Tue (11 Nov): Rain Likely. Snow Level Rising to 6000 Feet. 38/55 Wed (12 Nov): Light Rain Likely. Snow Level Rising to Near 7000 Feet. 43/56 Thu (13 Nov): Rain Turning to Showers. Snow Level Dropping to 4000 Feet. 48/54 Fri (14 Nov): Mostly Cloudy. Chance of Light Rain North Late. 42/55 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Fri Nov 7 12:24:21 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Fri, 07 Nov 2008 14:24:21 -0600 Subject: [willamette-fcst] Forecast - Friday, November 7th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. NOON UPDATE ...Next update Wednesday, November 12th, 2008 at 9:00am... Issued: Friday, November 7th, 2008 at 12:00pm. Burn Advisory: Agricultural burning is allowed. Suggested burn times are from now until 3:00pm. Straw stack burning is allowed from now until 3:00pm. Weather Discussion: A strong warm front stalled over western Washington Thursday with localy heavy rain continuing to fall over northwestern Washington through this morning. Rainfall amounts in the past 30 hours have been on the order of 4-7 inches across northwest Washington, from about Olympia northward. Locally heavy rain was still falling this morning north of Seattle. Meanwhile, with the warm front north of Oregon, mild southerly winds and cloudy skies made for a mild temperatures overnight with valley minimums in the middle to upper 50s. The late-morning ODA surface analysis showed the warm front stretching from the northern Washington Coast to just north of Seattle with weakening southerly gradients across northwestern Oregon. South winds had decreasing to 10-15 mph along the northern and central Oregon Coast and 5-10 mph in the Willamette Valley. Satellite imagery showed cloudy skies over all of Washington and the northern half of Oregon. extending from northwestern Washington back to a cold front, about 300 miles offshore. Clouds had also spred across all of western Oregon, in response to a slowly approaching cold front, about 250 miles offshore. Doppler radar showed a line of very light shower activity stretching from north-central Oregon to near Eugene with generally dry conditions over the remainder or Oregon. Temperatures were very mild with late-morning readings near 60 degrees across all of western Oregon and ranging from the mid 40s to near 60, with a few sunbreaks, east of the Cascades. The Salem sounding this morning showed significant warming above 6000 feet compared to Thursday. The freezing level had jumped to an unseasonably high 11,600 feet. Transport winds were still south-southwesterly but had decreased since Thursday. Western Oregon should remain in the \\\"warm sector\\\" of this storm system today with continued southerly wind and mild temperaturs. There will be some scattered light showers, but rainfall amounts will be mimimal. Mild southerly winds will lift high temperatures, once again, into the low 60s. Surface Winds: S 5-10 this afternoon. Transport Winds: SSW 20 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 2000 feet. Ventilation index 40. High Temperature: Salem\'s high temperature today will be near 62. Humidities: Minimum relative humidity will be near 75%. Sunrise/Sunset: Salem sunset tonight: 4:52pm; sunrise tomorrow: 7:01am. Extended Outlook: A Pacific cold front is forecast to bring more rain to the region tonight and Saturday, but snow levels should remain above the Cascades passes until the cold front pushes east of the region Saturday evening. A cool upper-level trough will bring showers to the region Sunday and Monday, with the snow level around 4000 feet. Another system is forecast to bring more rain Tuesday with rising snow levels. A warm front will likely be strong enough to continue the rain Wednesday, with snow levels rising to well above pass levels. The cold front is forecast to push through Wednesday night and lower snow levels to near the passes Thursday. We may get a break from the rain next Friday, with another system forecast to come onshore Friday night. Tomorrow (08 Nov): Rain Likely...Turning to Showers by Evening. 52/57 Sun (09 Nov): Showers. Snow Level 4000 Feet. 42/52 Mon (10 Nov): Decreasing Showers. Snow Level Near 4500 Feet. 38/52 Tue (11 Nov): Rain Likely. Snow Level Rising to 6000 Feet. 38/55 Wed (12 Nov): Light Rain Likely. Snow Level Rising to Near 7000 Feet. 43/56 Thu (13 Nov): Rain Turning to Showers. Snow Level Dropping to 4000 Feet. 48/54 Fri (14 Nov): Mostly Cloudy. Chance of Light Rain North Late. 42/55 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Wed Nov 12 09:05:07 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Wed, 12 Nov 2008 11:05:07 -0600 Subject: [willamette-fcst] Forecast - Wednesday, November 12th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Wednesday, November 12th, 2008 at 9:00am. Burn Advisory: Agricultural burning is allowed. Suggested burn times are from now until 3:00pm. Stack burning is not allowed. Weather Discussion: The most active weather in the country is right here in the Pacific Northwest this morning, with a strong westerly jet stream continuing to send abundant moisture onshore into Washington and northern Oregon. One-half to two-thirds of an inch of rain fell across the Willamette Valley Tuesday, as the first of two soaker-storms came onshore. Much greater amounts fell just to our north, with northwestern Washington getting 2-3 inches of rain. The Oregon coast generally picked up from one and one-half to three inches of rain Tuesday. Greater amounts fell in the coastal range and in the Cascades. Timberline Lodge has received over three inches of rain in the past 24 hours. Oregon has been on the warm (south) side of the jet stream the past few days, with freezing levels staying above 6000 feet. The morning sounding from Salem showed continued warming aloft, with the freezing level near 11,000 feet. Cascade pass temperatures were in the mid 40s this morning. Early-month snows, at higher elevations, were rapidly melting this morning with only 12 inches remaining at the 6000-foot elevation near Timberline Lodge. Only trace amounts of snow remained along the roadside at Willamette Pass with no snow visible from the Santiam Pass roadside camera. Satellite imagery showed a solid band of clouds stretching from Montana and Wyoming westward across Idaho, Washington and Oregon. Doppler radar continued to show moderate to heavy precipitation falling over much of western Washington with lighter rainfall over northern Oregon. Dry conditions generally prevailed south and east of a line from The Dalles to Salem to Brookings, on the southern Oregon Coast. The ODA surface analysis showed an east-to-west oriented cold front pushing into northwestern Washington with strong southerly pressure gradients extending southward well into Oregon. South winds were gusting to around 30 mph over much of the northern half of Oregon, on both sides of the Cascades. South winds were bringing very mild conditions to most of the state with mid-morning temperatures near 60 degrees from the coast, across the Willamette Valley, to the Columbia Basin of northeast Oregon. The cold front, to our north, is forecast to slowly sag southward today with rain expected to increase across northern and western Oregon this afternoon. The moisture feed into the frontal zone will be decreasing, as the front moves south, but locally heavy rainfall is still likely later today and tonight across northwestern Oregon...especially over the coast range and the Cascades. Additional rainfall totals, in the Willamette Valley, will likely range from one-half to one inch, before the rain tapers off Thursday morning. Greater amounts are likely along the coast and in the mountains. Blustery southerly winds will slowly turn more westerly and decrease later today and tonight. Temperatures will likely stay near 60 degrees today and slowly cool overnight, in the wake of the cold front. Surface Winds: S 10-20 G30 this morning, SSW 10-20 G30 this afternoon. Transport Winds: SSW 35 this morning, SW 35 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 1500 feet. Ventilation index 53. High Temperature: Salem\'s high temperature today will be near 60. Humidities: Minimum relative humidity will be near 87%. Sunrise/Sunset: Salem sunset tonight: 4:46pm; sunrise tomorrow: 7:08am. Extended Outlook: A major change, to a drier weather pattern, is forecast by all of the computer models, beginning tomorrow. A bulding upper-level ridge of high pressure, just off the west coast, will shut off the tropical moisture feed and turn the flow aloft northwesterly by Thursday afternoon. Temperatures will remain above normal, but valley highs will likely stay below 60 degrees. A little cooler air aloft should drop the freezing level to about 8000 feet. The upper-level ridge axis is forecast to move directly over Oregon Friday through Sunday. The surface flow will turn offshore for further drying of the air mass. The freezing level will likely jump back over 10,000 feet, with low-level temperature inversions developing. Easterly winds, from the Columbia Gorge, will help to clear morning fog from the north valley, but it could be fairly persistent in the south valley. Temperatures will vary considerably, depending on the extent and duration of valley fog, from day to day. The ridge if foreast to weaken and shift far enough east to allow a weak cold front to mix out the low-level temperature inversion Monday and bring back a chance of rain. Another ridge is forecast to dry things back out Tuesday and Wednesday with offshore flow re-developing. Tomorrow (13 Nov): Rain Tapering off with Partial Afternoon Clearing. 53/57 Fri (14 Nov): Morning Fog. Afternoon Clearing...Mainly North. 40/55 Sat (15 Nov): Morning Fog. Afternoon Clearing...Mainly North. 42/56 Sun (16 Nov): Morning Fog. Afternoon Clearing...Mainly North. 42/57 Mon (17 Nov): Increasing Clouds. Chance of Light Rain Late. 44/57 Tue (18 Nov): Rain Ending Early. Becoming Partly Cloudy. 41/53 Wed (19 Nov): Mostly Sunny. 35/51 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Thu Nov 13 08:59:45 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Thu, 13 Nov 2008 10:59:45 -0600 Subject: [willamette-fcst] Forecast - Thursday, November 13th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Thursday, November 13th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A cold front, laden with tropical moisture, moved southward across Washington Wednesday afternoon, dumping more than three inches of rain in sections of southwestern Washington. Heavy rain also fell along the Oregon Coast and in the Cascades, where one and one-half to three inches of rain were common. Astoria recorded three and one-third inches of rain in the past 24 hours, and Timberline Lodge picked up three and one-half inches. Meacham, in the northeast mountains, picked up over an inch of rain. The front lost strength, as it moved across Oregon overnight but was still was able to drop between one-half and one inch of rain over the Willamette Valley. The ODA surface analysis showed the cold front extending from southwestern Idaho across southern Oregon at mid-morning. Light rain was falling near the front, but skies were beginning to clear over the northern half or Oregon. The brisk southerly winds of the past couple of days decreased and turned northwesterly, in the wake of the cold front this morning. Cooler air was moving over northern Oregon this morning. The freezing level over Salem early this morning had only dropped to 8200 feet, but that has likely continued to come down. The 6000-foot temperature at Timberline Lodge cooled from near 40 degrees Wednesday afternoon to 30 degrees by this morning. Valley temperatures also staring to cool off this morning with some spots dipping into the upper 40s. A major change, to a drier weather pattern, will begin today. A bulding upper-level ridge of high pressure, just off the west coast, is turning the flow aloft northwesterly and shutting off the tropical moisture tap. Some sunshine was brightening things up this morning across the valley, even through temperatures were running close to 10 degrees cooler than yesterday at this time. A little sunshine should help temperatures climb into the upper 50s this afternoon, even with cooler air aloft. Northwesterly surface and transport winds will become more northerly later this afternoon, as high pressure continues to build over the region. Surface Winds: NW 5-10 this morning, NNW 5-10 this afternoon. Transport Winds: NW 10 this morning, N 7 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 2500 feet. Ventilation index 25. High Temperature: Salem\'s high temperature today will be near 59. Humidities: Minimum relative humidity will be near 57%. Sunrise/Sunset: Salem sunset tonight: 4:45pm; sunrise tomorrow: 7:09am. Extended Outlook: The strengthening upper-level ridge is forecast to move directly over Oregon Friday through Sunday, with weak weather systems riding over the top of it across Washington and southern British Columbia. Northerly surface flow may turn slightly offshore for further drying of the air mass. The freezing level will likely jump back over 10,000 feet, with low-level temperature inversions developing. Light easterly winds, near the Columbia Gorge, will help to clear morning fog from the north valley, but fog could be fairly persistent in the south valley. Weekend temperatures will vary considerably, depending on the extent and duration of valley fog. The Cascade foothills, coast range, and sections of the coast could be much warmer than in the Willamette Valley, due to low-level temperature inversions. The air aloft will be warm enough to support afternoon surface temperature well above 60 degrees, for areas that escape the fog. Fair skies and light winds will lead to colder overnight temperatures with much of the valley dropping into the 30s the next few nights. The ridge if forecast to weaken and shift far enough east to allow a weak cold front to approach the coastline late Monday. This system will likely weaken considerably, as it comes onshore early Tuesday, but it may be strong enough to bring a little rain to western Oregon and break up the fog. A transitory weak ridge is forecast to dry things out Wednesday, with less valley fog formation due to increasing offshore flow. A stronger weather system is forecast bring rain, cooler temperatures, and perhaps blustery conditions back to western Oregon next Thursday. Snow levels may drop to the Cascade passes by late Thursday, which would be welcome news for the ski industry but create winter driving conditions over the mountain passes. Tomorrow (14 Nov): Morning Fog. Afternoon Clearing...Mainly North. 36/54 Sat (15 Nov): Morning Fog. Afternoon Clearing...Mainly North. 37/57 Sun (16 Nov): Morning Fog. Afternoon Clearing...Mainly North. 39/58 Mon (17 Nov): Increasing Clouds. Chance of Light Rain Late. 41/59 Tue (18 Nov): Chance of Light Rain Early. Becoming Partly Cloudy. 43/53 Wed (19 Nov): Areas of AM Fog...Becoming Mostly Sunny. 35/56 Thu (20 Nov): Increasing Rain and Wind. Snow Level Dropping to 4000 Feet. 40/51 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Fri Nov 14 09:08:02 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Fri, 14 Nov 2008 11:08:02 -0600 Subject: [willamette-fcst] Forecast - Friday, November 14th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Friday, November 14th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A building upper-level ridge of high pressure cut off the tropical moisture feed into the Pacific Northwest and brought a little sunshine to western Oregon Thursday. Mild southerly winds turned northerly, which capped high temperatures in the 55-60 degree range across the Willamette Valley. The ridge strengthen overnight with the Salem sounding this morning showing considerble warming aloft since Thursday afternoon. The freezing level had jumped back to near 12,000 feet over western Oregon. Meanwhile, fair skies and light winds allowed surface temperatures to drop into the mid 30s across the valley, by early this morning, with areas of fog forming. A strengthening low-level temperature inversion will keep mixing heights below 1500 feet today with light northeasterly transport winds this morning turning more southeasterly this afternoon. Satellite imagery showed clouds streaming over the top of the ridge of high pressure across Washington with only a few high clouds slipping south of the Washington/Oregon border. Areas of fog and low clouds formed overnight in the valleys of southwestern Oregon and in the southern Willamette Valley. The remainder of the state had sunshine this morning. The ODA surface analysis showed high pressure over eastern Washington and northeast Oregon with a building thermal trough along the southern Oregon Coast. Offshore gradients were generating brisk easterly winds at the western end of the Columbia Gorge. Troutdale was getting east winds gusting to near 25 mph. Dry easterly flow helped the north valley stay clear of the fog and low clouds this morning, but there was a considerable amount of fog and low cloudiness, showing up on visible satellite imagery, across Linn and Lane Counties. Valley temperatures ranged from the mid 30s, in clear areas, to the low 40s in foggy zones at mid-morning. Dry easterly flow was dropping off the coast range and keeping skies clear along the Oregon Coast. Newport had easterly winds, sunny skies, and temperatures in the mid 40s this morning. Continued offshore flow will help to clear the fog and low clouds from the southern valleys this afternoon, with sunshine over the remainder of the state. Valley highs will range from near 50, where fog is more persistent in the south valley, to near 60 along the northern Cascade and coastal range foothills and along the coast. Fair skies and continued light offshore flow will allow areas of fog and low clouds to reform overnight...especially in the southern Willamette Valley. Gorge winds will help the north valley stay more clear. Minimum temperatures will dip locally to near freezing in clear areas and into the mid to upper 30s where fog forms. Surface Winds: NE 0-4 this morning, SE 0-4 this afternoon. Transport Winds: NE 4 this morning, SE 4 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 1500 feet. Ventilation index 6. High Temperature: Salem\'s high temperature today will be near 55. Humidities: Minimum relative humidity will be near 57%. Sunrise/Sunset: Salem sunset tonight: 4:44pm; sunrise tomorrow: 7:10am. Extended Outlook: The strong and broad upper-level ridge is forecast to remain over Oregon through Monday. Weak weather systems riding over the top of the ridge will spread some middle and high clouds over Washington and southern British Columbia. Light offshore flow will aid in drying the air mass. The freezing level will remain well over 10,000 feet, with the low sun-angle this time of year leading to the development of strong low-level temperature inversions. Light easterly winds, near the Columbia Gorge, will help to clear morning fog from the north valley, but valley fog could be fairly persistent south of about Salem. Weekend temperatures will vary considerably, depending on the extent and duration of valley fog. The Cascade foothills, coast range, and sections of the coast could climb into the low to mid 60s, while sections of the Willamette Valley stay in the low to mid 50s with persistent fog. Fair skies and light winds will drop overnight temperatures into the 30s the next few nights. The ridge is forecast to flatten and beging shifting east Monday. A weakening cold front may make it onshore about Tuesday but will not likely produce much, if any, rainfall. The ridge is forecast to rebuild Wednesday, with increasing offshore flow at the surface providing a little sunshine. By Thursday, the ridge will likely give way to what will appears to be a series of Pacific stroms, which would improve ventilation conditions for stack burning. Snow levels may drop to the Cascade passes by Friday. That would be welcome news for the ski industry but initiate winter driving conditions, for travelers, over the mountain passes. Tomorrow (15 Nov): Morning Fog...Mainly South. Becoming Mostly Sunny. 34/57 Sun (16 Nov): Morning Fog. Afternoon Clearing...Mainly North. 36/58 Mon (17 Nov): Morning Fog. Afternoon Clearing...Mainly North. 39/57 Tue (18 Nov): Areas of AM Fog. Partly Cloudy. 40/56 Wed (19 Nov): Partly Cloudy. 39/56 Thu (20 Nov): Chance of Rain. 39/54 Fri (21 Nov): Rain Likely. Snow Level Dropping to 4000 Feet. 38/48 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Mon Nov 17 09:05:34 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Mon, 17 Nov 2008 11:05:34 -0600 Subject: [willamette-fcst] Forecast - Monday, November 17th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Monday, November 17th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: The strong and broad upper-level ridge built over the Pacific Northwest this past weekend with southerly flow aloft spreading middle and high clouds across Washington and much of Oregon. The air mass aloft became very warm with the freezing level rising to about 13,000 feet. Afternoon temperatures were in the low 60s, as high as 6000 feet, in the Cascades. Light easterly winds helped keep fog from forming in the north valley and along the coast, where ample sunshine allowed temperatures to climb into the upper 50s and 60s bot days. However, strengthening low-level temperature inversions, in the central and southern Willamette Valley, led to more persistent fog each day. High temperatures managed to climb into the mid to upper 50s Saturday but were held in the mid to upper 40s Sunday. Overnight temperatures in the valley were mostly in the 30s. The morning sounding over Salem showed a very strong low-level inversion with surface temperatures near 40 degrees and 2000-foot temperatures in the upper 60s. That led to the formation of widespread and locally dense fog over much of the Willamette Valley this morning. Dry easterly flow was keeping fog from forming near the Columbia Gorge and west of the coast range. The upper-level ridge will maintain stagnant air conditions over Oregon today. The ridge axis will shift to over Idaho by this afternoon with increasing southerly flow aloft. That will increase the middle and high clouds over Oregon, but the strong low-level temperature inversion will continue. Fog and low clouds will be persistent in the central and south valley again today with filtered sunshine in the north valley. High temperatures will vary considerably, with sunny areas near 60 degrees and foggy locations not climbing out of the 40s. Surface winds will be light and variable. Surface Winds: Var 0-4 this morning, Var 0-5 this afternoon. Transport Winds: S 4 this morning, SSW 6 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 800 feet. Ventilation index 5. High Temperature: Salem\'s high temperature today will be near 50. Humidities: Minimum relative humidity will be near 80%. Sunrise/Sunset: Salem sunset tonight: 4:41pm; sunrise tomorrow: 7:14am. Extended Outlook: A weakening cold front may make it onshore about Tuesday but not likely produce any rainfall. It may promote enough mixing of the air mass to raise temperatuers in some areas of the valley. The ridge is forecast to rebuild Wednesday, with areas of dense fog reforming...mainly in the south valley. A stronger cold front is forecast to move onshore Wednesday night. Rain will likely spread across western Oregon Thursday, which would improve ventilation conditions. Temperatures will warm in the central and south valley, while the air aloft cools. Snow levels may drop to the Cascade passes by Thursday afternoon. Another system may bring more rain and mountain snow by late Friday. The ridge appears as if it may build back over the region this weekend, but that is getting beyond to range of the computer models. Tomorrow (18 Nov): Areas of Fog. Mostly Cloudy. 38/55 Wed (19 Nov): Areas of Fog. Mostly Cloudy. 39/56 Thu (20 Nov): Rain Likely. Snow Level Dropping to 4000 Feet. 44/53 Fri (21 Nov): Mostly Cloudy. Chance of Rain Late. Snow Level 6000 Feet. 41/57 Sat (22 Nov): Mostly Cloudy. 40/52 Sun (23 Nov): Areas of Fog. Partly Sunny. 37/55 Mon (24 Nov): Areas of Fog. Partly Sunny. 37/55 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Tue Nov 18 09:01:39 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Tue, 18 Nov 2008 11:01:39 -0600 Subject: [willamette-fcst] Forecast - Tuesday, November 18th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Tuesday, November 18th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: Increasing southerly flow aloft helped to clear the fog and low clouds from sections of the southern Willamette Valley Monday afternoon and mix down very warm air aloft to the surface. Eugene tied a daily record high temperature with 70 degrees (previously set in 1932). In central Oregon, Redmond shattered their previous daily record high, for November 17th, by soaring to 75 degrees (old record 66 degrees set in 1976). Eastern Oregon temperatures also got into the record books Monday. Meacham, in northeast Oregon, set a daily record with a high of 58 degrees (old record 57 set in 1949). Monday was also unseasonably warm along the coast. Tillamook hit the 70-degree mark and Newport climbed to 66. There was quite a contrast in afternoon temperatures across the Willamette Valley Monday. While much of the south valley warmed well into the 60s, including a 66-degree high at Corvallis, fog was slow to clear in areas of the north valley. McMinnville only managed 51 degrees, and Salem split the difference with a high of 58. A weakening cold front moved onto the north coast early this morning, but it was not strong enough to keep areas of rather dense fog from forming over sections of the Willamette Valley...mainly from about Aurora to Corvallis. The front will fall apart, as it drifts southeastward, across western Oregon, today. Southwesterly flow aloft will maintain mostly cloudy skies, above the fog layer. The Salem sounding showed significant cooling aloft since Monday, so temperatures should be more uniform across the valley this afternoon. Most areas should see highs today in the mid to upper 50s with light winds. There is a slight chance of sprinkles over extreme northwest Oregon, otherwise it should remain dry across the state today. Surface Winds: Var 0-5 this morning, N 0-5 this afternoon. Transport Winds: Var 3 this morning, N 3-6 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 1200 feet. Ventilation index 4. High Temperature: Salem\'s high temperature today will be near 55. Humidities: Minimum relative humidity will be near 66%. Sunrise/Sunset: Salem sunset tonight: 4:40pm; sunrise tomorrow: 7:16am. Extended Outlook: The upper-level ridge is forecast to rebuild Wednesday, with areas of dense fog reforming...mainly in the central and south valley. A developing offshore flow, from the Columbia Gorge, should help to keep dense fog out of the extreme north valley. Skies will remain partly to mostly cloudy, above the fog layer. A stronger cold front should increase the offshore flow enough to keep widespread fog from forming Wednesday night. Rain will likely spread across western Oregon Thursday morning, with cooler air aloft improving ventilation conditions. Rain will be heaviest in the north valley, where amounts could top one-half inch. Valley temperatures will be near normal, even with significant cooling aloft. Snow levels may drop enough, by Thursday afternoon, for some accumulating snow over the Cascade passes. A warm front, from the next system, will spread clouds across western Oregon Friday, but rainfall should stay mostly north of the state. The cold front could extend far enough south to bring light rain to much of western Oregon Saturday. A strong upper-level ridge will likely bring a return of dry weather Sunday through Tuesday with a little sunshine. Low-level temperature inversions will make for poor ventilation conditions and lead to valley fog formation. Outflow, from the Columbia Gorge, should help keep widespread fog from forming in the north valley, but it could become persistent in the central and south valley. Tomorrow (19 Nov): Areas of Fog. Increasing Clouds. Chance of Rain Late. 39/56 Thu (20 Nov): Rain Likely. Snow Level Dropping to 4-5000 Feet. 43/52 Fri (21 Nov): Mostly CLoudy. Chance of Light Rain North. Snow Level 7000 Feet. 36/52 Sat (22 Nov): Mostly Cloudy. Chance of Light Rain. Snow Level 4-5000 Feet. 40/52 Sun (23 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 37/52 Mon (24 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 37/52 Tue (25 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 37/52 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Wed Nov 19 09:13:06 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Wed, 19 Nov 2008 09:13:06 -0800 Subject: [willamette-fcst] Willamette Valley Agricultural/Burning Forecast Message-ID: Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Wednesday, November 19th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A very weak cold front spread considerable middle and high clouds across Oregon Tuesday but was too weak to break the strong low-level temperture inversion over the Willamette Valley. Areas of morning fog gave way to filtered sunshine Tuesday afternoon. Winds remained light and valley highs climbed into the mid to upper 50s. An upper-level ridge began rebuilding over Oregon last night with the surface cold front stalling over Oregon. Fog and low clouds redeveloped across much of the Willamette Valley overnight and in some of the valleys of southwestern and eastern Oregon. Southwesterly flow aloft was continuing to spread middle and high clouds across most of the state this morning. The ODA surface analysis showed increasing offshore flow across Oregon, and easterly winds were gusting to near 30 mph at Troutdale, in the western Columbia Gorge, by mid-morning. That should help to keep dense fog out of the extreme north valley today, although some fog was being reported in western parts of the north valley, near Hillsboro. Easterly winds were also keeping fog away from the coastline. Satellite imagery showed middle and high clouds covering most of the state. A very weak upper-level disturbance is forecast to move over Oregon today, in the southwesterly flow aloft, so only some filtered sunshine can be expected, once the areas of morning fog begin to lift. The offshore flow will increase across western Oregon with continued dry easterly outflow, from the Columbia Gorge, fanning out across the north valley. Winds should remain light in the central and south valley. The sounding over Salem this morning was similar to Tuesday morning. Warm air aloft is creating a very stable air mass with continued poor ventilation conditions over Oregon. Surface temperatures this morning ranged from the upper 20s to the low 40s east of the Cascades and were generally in the 40s across western Oregon. Highs today should be mostly in the mid 50s across the Willamette Valley and along the coast. Central and Eastern Oregon temperatures will climb into the 50s and low 60s. An approaching cold front will further increase the offshore flow tonight, which should keep fog from forming in the north valley. Southeastery winds may develop enough to keep fog from forming in the central and south valley. In any case, middle and high clouds, from the approaching weather system, will begin spreading onshore by Thursday morning with rain possible by daybreak. Surface Winds: N 0-3 this morning, N 0-3 this afternoon. Transport Winds: N 3 this morning, N 3 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 500 feet. Ventilation index 2. High Temperature: Salem\'s high temperature today will be near 54. Humidities: Minimum relative humidity will be near 71%. Sunrise/Sunset: Salem sunset tonight: 4:39pm; sunrise tomorrow: 7:17am. Extended Outlook: Rain will likely spread across western Oregon Thursday morning, with cooler air aloft improving ventilation conditions. Rain will be heaviest in the north valley, where amounts could top one-half inch. Even with significant cooling aloft, valley highs will only fall to near normal. Snow levels will quickly drop to about 4000 feet, by midday Thursday, with a few inches of snow likely over the Cascade passes Thursday afternoon and night. A warm front will spread clouds across western Oregon Friday. Rainfall appears as if it will stay north of Oregon, until a cold front approaches the coastline Friday evening. The cold front will sweep across western Oregon early Saturday with a few showers lingering into Saturday night. Rainfall from this system will generally be less than one-quarter of an inch across the Willamette Valley with the greatest totals in the northern Cascade foothills. A strong upper-level ridge will likely bring a return of dry weather Sunday through Tuesday with a little sunshine...mainly in the north valley. Low-level temperature inversions will make for poor ventilation conditions and lead to valley fog formation. Outflow, from the Columbia Gorge, should help keep widespread fog from forming in the north valley, but fog could become persistent in the central and south valley. The ridge is forecast to begin breaking down about Tuesday of next week with increasing southwesterly flow aloft. Middle and high clouds will likely spread over the region Tuesday with a threat of light rain moving onshore by Tuesday night. A weak cold front may bring light rain to the valley next Wednesday. This system may be cold enough to bring some snow to the ski areas, just in time for the Thanksgiving holiday weekend. Tomorrow (20 Nov): Rain Likely. Snow Level Dropping to 4-5000 Feet. 45/51 Fri (21 Nov): Mostly CLoudy. Chance of Light Rain North. Snow Level 5000 Feet. 36/52 Sat (22 Nov): Light Rain AM...Decreasing Showers PM. Snow Level 4-5000 Feet. 41/51 Sun (23 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 35/55 Mon (24 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 37/52 Tue (25 Nov): Areas of Fog...Increasing Clouds. 37/54 Wed (26 Nov): Chance of Light Rain and Mountain Snow. Snow Level 4000 Feet. 41/49 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Wed Nov 19 11:59:46 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Wed, 19 Nov 2008 13:59:46 -0600 Subject: [willamette-fcst] Forecast - Wednesday, November 19th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. NOON UPDATE Issued: Wednesday, November 19th, 2008 at 12:00pm. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A warm upper-level ridge remains over the region today. Warm air aloft is creating a very stable air mass with continued poor ventilation conditions over Oregon. Fog and low clouds redeveloped across much of the Willamette Valley overnight, with low cloudiness prevailing across the valley late this morning. A weak upper-level disturbance, in southwesterly flow aloft, was moving onto the Oregon Coast late this morning and thickening the cloud-cover over the state. The ODA surface analysis showed increasing offshore flow across Oregon. Easterly winds were gusting to over 30 mph at Troutdale, in the western Columbia Gorge, late this morning. Easterly winds were also dropping off the coastal range to the Oregon beaches. However, winds were still light and variable in the Willamette Valley with persistent areas of fog. Late-morning satellite imagery showed cloduds covering most of the state with thicker cloud-cover moving over western Oregon. Doppler radar showed an area of sprinkles moving northeastward into the southern Willamette Valley. Temperatures had warmed into the upper 40s and low 50s across western Oregon. Skies were partly to mostly cloudy east of the Cascades with temperatures mostly in the 40s. Skies will reamin cloudy today with a chance of sprinkles across western Oregon this afternoon. Offshore flow will continue to produce gusty east winds near the west end of the Columbia Gorge. Winds should remain light in the central and south valley. Highs today should be mostly in the mid 50s across western Oregon. Central and Eastern Oregon temperatures will climb into the 50s and low 60s under mostly cloudy skies. There may be some breaks in the cloud-cover tonight, ahead of an approaching cold front that will increase the clouds again by Thursday morning. Continued offshore flow should keep widespread fog from forming in the north valley tonight, but areas of fog will likely reform in the central and south valley. Surface Winds: N 0-3 this afternoon. Transport Winds: N 3 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 500 feet. Ventilation index 2. High Temperature: Salem\'s high temperature today will be near 54. Humidities: Minimum relative humidity will be near 71%. Sunrise/Sunset: Salem sunset tonight: 4:39pm; sunrise tomorrow: 7:17am. Extended Outlook: Rain will likely spread across western Oregon Thursday morning, with cooler air aloft improving ventilation conditions. Rain will be heaviest in the north valley, where amounts could top one-half inch. Even with significant cooling aloft, valley highs will only fall to near normal. Snow levels will quickly drop to about 4000 feet, by midday Thursday, with a few inches of snow likely over the Cascade passes Thursday afternoon and night. A warm front will spread clouds across western Oregon Friday. Rainfall appears as if it will stay north of Oregon, until a cold front approaches the coastline Friday evening. The cold front will sweep across western Oregon early Saturday with a few showers lingering into Saturday night. Rainfall from this system will generally be less than one-quarter of an inch across the Willamette Valley with the greatest totals in the northern Cascade foothills. A strong upper-level ridge will likely bring a return of dry weather Sunday through Tuesday with a little sunshine...mainly in the north valley. Low-level temperature inversions will make for poor ventilation conditions and lead to valley fog formation. Outflow, from the Columbia Gorge, should help keep widespread fog from forming in the north valley, but fog could become persistent in the central and south valley. The ridge is forecast to begin breaking down about Tuesday of next week with increasing southwesterly flow aloft. Middle and high clouds will likely spread over the region Tuesday with a threat of light rain moving onshore by Tuesday night. A weak cold front may bring light rain to the valley next Wednesday. This system may be cold enough to bring some snow to the ski areas, just in time for the Thanksgiving holiday weekend. Tomorrow (20 Nov): Rain Likely. Snow Level Dropping to 4-5000 Feet. 45/51 Fri (21 Nov): Mostly CLoudy. Chance of Light Rain North. Snow Level 5000 Feet. 36/52 Sat (22 Nov): Light Rain AM...Decreasing Showers PM. Snow Level 4-5000 Feet. 41/51 Sun (23 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 35/55 Mon (24 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 37/52 Tue (25 Nov): Areas of Fog...Increasing Clouds. 37/54 Wed (26 Nov): Chance of Light Rain and Mountain Snow. Snow Level 4000 Feet. 41/49 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Wed Nov 19 09:16:09 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Wed, 19 Nov 2008 11:16:09 -0600 Subject: [willamette-fcst] Forecast - Wednesday, November 19th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Wednesday, November 19th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A very weak cold front spread considerable middle and high clouds across Oregon Tuesday but was too weak to break the strong low-level temperture inversion over the Willamette Valley. Areas of morning fog gave way to filtered sunshine Tuesday afternoon. Winds remained light and valley highs climbed into the mid to upper 50s. An upper-level ridge began rebuilding over Oregon last night with the surface cold front stalling over Oregon. Fog and low clouds redeveloped across much of the Willamette Valley overnight and in some of the valleys of southwestern and eastern Oregon. Southwesterly flow aloft was continuing to spread middle and high clouds across most of the state this morning. The ODA surface analysis showed increasing offshore flow across Oregon, and easterly winds were gusting to near 30 mph at Troutdale, in the western Columbia Gorge, by mid-morning. That should help to keep dense fog out of the extreme north valley today, although some fog was being reported in western parts of the north valley, near Hillsboro. Easterly winds were also keeping fog away from the coastline. Satellite imagery showed middle and high clouds covering most of the state. A very weak upper-level disturbance is forecast to move over Oregon today, in the southwesterly flow aloft, so only some filtered sunshine can be expected, once the areas of morning fog begin to lift. The offshore flow will increase across western Oregon with continued dry easterly outflow, from the Columbia Gorge, fanning out across the north valley. Winds should remain light in the central and south valley. The sounding over Salem this morning was similar to Tuesday morning. Warm air aloft is creating a very stable air mass with continued poor ventilation conditions over Oregon. Surface temperatures this morning ranged from the upper 20s to the low 40s east of the Cascades and were generally in the 40s across western Oregon. Highs today should be mostly in the mid 50s across the Willamette Valley and along the coast. Central and Eastern Oregon temperatures will climb into the 50s and low 60s. An approaching cold front will further increase the offshore flow tonight, which should keep fog from forming in the north valley. Southeastery winds may develop enough to keep fog from forming in the central and south valley. In any case, middle and high clouds, from the approaching weather system, will begin spreading onshore by Thursday morning with rain possible by daybreak. Surface Winds: N 0-3 this morning, N 0-3 this afternoon. Transport Winds: N 3 this morning, N 3 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 500 feet. Ventilation index 2. High Temperature: Salem\'s high temperature today will be near 54. Humidities: Minimum relative humidity will be near 71%. Sunrise/Sunset: Salem sunset tonight: 4:39pm; sunrise tomorrow: 7:17am. Extended Outlook: Rain will likely spread across western Oregon Thursday morning, with cooler air aloft improving ventilation conditions. Rain will be heaviest in the north valley, where amounts could top one-half inch. Even with significant cooling aloft, valley highs will only fall to near normal. Snow levels will quickly drop to about 4000 feet, by midday Thursday, with a few inches of snow likely over the Cascade passes Thursday afternoon and night. A warm front will spread clouds across western Oregon Friday. Rainfall appears as if it will stay north of Oregon, until a cold front approaches the coastline Friday evening. The cold front will sweep across western Oregon early Saturday with a few showers lingering into Saturday night. Rainfall from this system will generally be less than one-quarter of an inch across the Willamette Valley with the greatest totals in the northern Cascade foothills. A strong upper-level ridge will likely bring a return of dry weather Sunday through Tuesday with a little sunshine...mainly in the north valley. Low-level temperature inversions will make for poor ventilation conditions and lead to valley fog formation. Outflow, from the Columbia Gorge, should help keep widespread fog from forming in the north valley, but fog could become persistent in the central and south valley. The ridge is forecast to begin breaking down about Tuesday of next week with increasing southwesterly flow aloft. Middle and high clouds will likely spread over the region Tuesday with a threat of light rain moving onshore by Tuesday night. A weak cold front may bring light rain to the valley next Wednesday. This system may be cold enough to bring some snow to the ski areas, just in time for the Thanksgiving holiday weekend. Tomorrow (20 Nov): Rain Likely. Snow Level Dropping to 4-5000 Feet. 45/51 Fri (21 Nov): Mostly CLoudy. Chance of Light Rain North. Snow Level 5000 Feet. 36/52 Sat (22 Nov): Light Rain AM...Decreasing Showers PM. Snow Level 4-5000 Feet. 41/51 Sun (23 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 35/55 Mon (24 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 37/52 Tue (25 Nov): Areas of Fog...Increasing Clouds. 37/54 Wed (26 Nov): Chance of Light Rain and Mountain Snow. Snow Level 4000 Feet. 41/49 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Wed Nov 19 09:04:33 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Wed, 19 Nov 2008 11:04:33 -0600 Subject: [willamette-fcst] Forecast - Wednesday, November 19th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Wednesday, November 19th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A very weak cold front spread considerable middle and high clouds across Oregon Tuesday but was too weak to break the strong low-level temperture inversion over the Willamette Valley. Areas of morning fog gave way to filtered sunshine Tuesday afternoon. Winds remained light and valley highs climbed into the mid to upper 50s. An upper-level ridge began rebuilding over Oregon last night with the surface cold front stalling over Oregon. Fog and low clouds redeveloped across much of the Willamette Valley overnight and in some of the valleys of southwestern and eastern Oregon. Southwesterly flow aloft was continuing to spread middle and high clouds across most of the state this morning. The ODA surface analysis showed increasing offshore flow across Oregon, and easterly winds were gusting to near 30 mph at Troutdale, in the western Columbia Gorge, by mid-morning. That should help to keep dense fog out of the extreme north valley today, although some fog was being reported in western parts of the north valley, near Hillsboro. Easterly winds were also keeping fog away from the coastline. Satellite imagery showed middle and high clouds covering most of the state. A very weak upper-level disturbance is forecast to move over Oregon today, in the southwesterly flow aloft, so only some filtered sunshine can be expected, once the areas of morning fog begin to lift. The offshore flow will increase across western Oregon with continued dry easterly outflow, from the Columbia Gorge, fanning out across the north valley. Winds should remain light in the central and south valley. The sounding over Salem this morning was similar to Tuesday morning. Warm air aloft is creating a very stable air mass with continued poor ventilation conditions over Oregon. Surface temperatures this morning ranged from the upper 20s to the low 40s east of the Cascades and were generally in the 40s across western Oregon. Highs today should be mostly in the mid 50s across the Willamette Valley and along the coast. Central and Eastern Oregon temperatures will climb into the 50s and low 60s. An approaching cold front will further increase the offshore flow tonight, which should keep fog from forming in the north valley. Southeastery winds may develop enough to keep fog from forming in the central and south valley. In any case, middle and high clouds, from the approaching weather system, will begin spreading onshore by Thursday morning with rain possible by daybreak. Surface Winds: N 0-3 this morning, N 0-3 this afternoon. Transport Winds: N 3 this morning, N 3 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 500 feet. Ventilation index 2. High Temperature: Salem\'s high temperature today will be near 54. Humidities: Minimum relative humidity will be near 71%. Sunrise/Sunset: Salem sunset tonight: 4:39pm; sunrise tomorrow: 7:17am. Extended Outlook: Rain will likely spread across western Oregon Thursday morning, with cooler air aloft improving ventilation conditions. Rain will be heaviest in the north valley, where amounts could top one-half inch. Even with significant cooling aloft, valley highs will only fall to near normal. Snow levels will quickly drop to about 4000 feet, by midday Thursday, with a few inches of snow likely over the Cascade passes Thursday afternoon and night. A warm front will spread clouds across western Oregon Friday. Rainfall appears as if it will stay north of Oregon, until a cold front approaches the coastline Friday evening. The cold front will sweep across western Oregon early Saturday with a few showers lingering into Saturday night. Rainfall from this system will generally be less than one-quarter of an inch across the Willamette Valley with the greatest totals in the northern Cascade foothills. A strong upper-level ridge will likely bring a return of dry weather Sunday through Tuesday with a little sunshine...mainly in the north valley. Low-level temperature inversions will make for poor ventilation conditions and lead to valley fog formation. Outflow, from the Columbia Gorge, should help keep widespread fog from forming in the north valley, but fog could become persistent in the central and south valley. The ridge is forecast to begin breaking down about Tuesday of next week with increasing southwesterly flow aloft. Middle and high clouds will likely spread over the region Tuesday with a threat of light rain moving onshore by Tuesday night. A weak cold front may bring light rain to the valley next Wednesday. This system may be cold enough to bring some snow to the ski areas, just in time for the Thanksgiving holiday weekend. Tomorrow (20 Nov): Rain Likely. Snow Level Dropping to 4-5000 Feet. 45/51 Fri (21 Nov): Mostly CLoudy. Chance of Light Rain North. Snow Level 5000 Feet. 36/52 Sat (22 Nov): Light Rain AM...Decreasing Showers PM. Snow Level 4-5000 Feet. 41/51 Sun (23 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 35/55 Mon (24 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 37/52 Tue (25 Nov): Areas of Fog...Increasing Clouds. 37/54 Wed (26 Nov): Chance of Light Rain and Mountain Snow. Snow Level 4000 Feet. 41/49 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Thu Nov 20 09:08:23 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Thu, 20 Nov 2008 11:08:23 -0600 Subject: [willamette-fcst] Forecast - Thursday, November 20th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Thursday, November 20th, 2008 at 9:00am. Burn Advisory: Agricultural burning is allowed. Suggested burn times are from 10:00am until 2:30pm. Straw stack burning is allowed, for dry stacks, from 10:00am until 2:30pm. Weather Discussion: Clearing skies Wednesday evening allowed fog to reform across the central and southern Willamette Valley overnight. Easterly outflow, from the Columbia Gorge, kept fog from forming in the Portland area, north of about Wilsonville. It was another relatively mild night, for mid-November, with temperatures staying mostly in the 40s. Hillsboro was one of the colder spots with a minimum of 36 degrees. A cold front moved onshore early this morning and brought a brief burst of locally heavy rain and gusty south winds to the Willamette Valley starting just before daybreak. The frontal passage produced south winds gusting to near 25 mph in the south valley and 30 mph in the north valley this morning. Rainfall totals, by mid-morning, were generally around two-tenths of an inch across the valley. Satellite imagery showed the cloud-band associated with the cold front extending from the north coast through the northern Willamette Valley to the centra Cascades at mid-morning. Doppler radar showed the heaviest rain from near Kelso, Washington to Salem, Oregon. The entire frontal system was quickly moving northeastward. The ODA surface analysis showed a fairly strong south-to-north pressure gradient along and west of the cold front, so it will likely stay a little blustery at times across western Oregon today. Significant cooling aloft will wipe out the low-level temperature inversion that has been over the valley for several days and will greatly improve ventilation conditions today. It has also dropped to snow level from 7000 feet to about 4000 this morning. ODOT cameras confirmed that rain had changed to snow, over the Cascade passes, by mid-morning, with pass temperatures in the low 30s. A winter weather advisory is in effect for the Cascade passes, until 10 pm, for up to 7 inches of new snow. A cold upper-level trough will follow the cold front onshore this afternoon and keep showers going across western Oregon. There is even a slight chance of a thundershower. High temperatures will struggle to climb much above 50 degrees, which is about normal for mid-November. Southwesterly winds will be gusty near showers. The showers should quickly taper off this evening, as the upper-level trough moves east of the region. Clearing skies will allow areas of fog to form with mimimum temperatures mostly in the mid to upper 30s. Surface Winds: SSW 10-15 G25 this morning, SW 10-15 G25 this afternoon. Transport Winds: S 25 this morning, SW 28 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 3000 feet. Ventilation index 84. High Temperature: Salem\'s high temperature today will be near 51. Humidities: Minimum relative humidity will be near 80%. Sunrise/Sunset: Salem sunset tonight: 4:38pm; sunrise tomorrow: 7:18am. Extended Outlook: A warm front will spread clouds across western Oregon Friday. Rainfall appears as if it will stay north of Oregon, until a cold front approaches the coastline Friday evening. The cold front will sweep across western Oregon early Saturday with a few showers lingering into Saturday night. Rainfall from this system will generally be less than one-quarter of an inch across the Willamette Valley with the greatest totals in the northern Cascade foothills. A strong upper-level ridge will likely bring a return of dry weather Sunday and Monday with a little sunshine...mainly in the north valley. Low-level temperature inversions will make for poor ventilation conditions and lead to valley fog formation. Outflow, from the Columbia Gorge, should help keep widespread fog from forming in the north valley, but fog could become persistent in the central and south valley. The ridge is forecast to begin breaking down about Tuesday of next week with increasing southwesterly flow aloft. A weak cold front may bring light rain to the valley Tuesday with another ridge bringing back dry weather for Thanksgiving. Tomorrow (21 Nov): Mostly Cloudy. Rain Likely Late. Snow Level 5000 Feet. 36/50 Sat (22 Nov): Light Rain AM...Decreasing Showers PM. Snow Level 4-5000 Feet. 41/51 Sun (23 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 33/51 Mon (24 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 37/53 Tue (25 Nov): Chance of Light Rain. Snow Level 4-5000 Feet. 38/53 Wed (26 Nov): Partly Sunny. 35/51 Thu (27 Nov): Partly Sunny. 35/52 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Fri Nov 21 09:03:21 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Fri, 21 Nov 2008 11:03:21 -0600 Subject: [willamette-fcst] Forecast - Friday, November 21st, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Friday, November 21st, 2008 at 9:00am. Burn Advisory: Agricultural burning is allowed. Suggested burn times are from now until 2:30pm. Stack burning is not allowed. Weather Discussion: A vigorous cold front moved across Western Oregon Thursday morning...following by numerous showers Thursday afternoon. Rainfall totals were fairly uniform, around one-half inch, across most of western Oregon. Showers tapered off overnight with clearing skies allowing temperatures to fall well into the 30s, with widespread fog reforming, across the Willamette Valley. The morning sounding over Salem revealed a much colder air mass, in the wake of Thursday\'s cold front. The freezing level had dropped to just 4500 feet, from 8300 feet on Thursday. Some valley locations dipped to near or slightly below the freezing mark this morning. Eugene had freezing fog with a low of just 30 degrees. Hillsboro dropped to 32 degrees, while McMinnville, Salem, and Corvallis bottomed out at 34. Those cool surface temperatures created a low-level temperature inversion extedning up to about 1000 feet. Satelite imagery showed middle and high clouds, associated with a warm front, spreading over western Washington and extreme northwest Oregon. The cold front was still about 400 miles offshore. Rain will stay north of Oregon, until the cold front approaches the coastline this evening. Pesistent valley fog will keep high temperatures from climbing much above 50 degrees, with some areas likely staying in the 40s. Warming aloft will likely maintain the low-level inversion today, so stack burning was not allowed. Increasing southeasterly winds will likely begin lifting the fog late this afternoon. Rain should move onshore shortly after sunset and into the valley this evening. The cold front is forecast to move across western Oregon in the pre-dawn hours Saturday. Surface Winds: SE 0-5 this morning, SSE 5-10 this afternoon. Transport Winds: SE 6 this morning, S 10 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 1000 feet. Ventilation index 10. High Temperature: Salem\'s high temperature today will be near 50. Humidities: Minimum relative humidity will be near 68%. Sunrise/Sunset: Salem sunset tonight: 4:38pm; sunrise tomorrow: 7:20am. Extended Outlook: After some early moring rain, a weak upper-level trough will keep a chance of showers across western Oregon though Saturday afternoon. This will quickly dry out Saturday evening. Total rainfall from this system will be mostly less than one-quarter of an inch, with the greatest amounts in the northern Cascade foothills. A strong upper-level ridge will likely bring a return of dry weather Sunday and Monday with a little sunshine...mainly in the north valley. Low-level temperature inversions will make for poor ventilation conditions and lead to valley fog formation. Outflow, from the Columbia Gorge, should help keep widespread fog from forming in the north valley, but fog could become persistent in the central and south valley. The ridge is forecast to begin breaking down about Tuesday with increasing southwesterly flow aloft. A developing split-flow pattern in the jet stream will likely take most of the punch out of a cold front, as it comes onshore Tuesday afternoon. A transitory ridge is forecast to bring back dry conditions Wednesday. The computer model solutions diverge starting on Thanksgiving. Due to the variety of stuffing be put into the long-range forecast, it could turn out to be a real turkey. There is a reasonable chance, however, that a strong upper-level ridge will build close enough to the coastline to bring northeasterly flow aloft by Friday. That would bring rare November sunshine to most of the state, which I am sure we would gobble up. Tomorrow (22 Nov): Light Rain AM...Decreasing Showers PM. Snow Level 4-5000 Feet. 40/51 Sun (23 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 33/50 Mon (24 Nov): Areas of Fog...Mainly Central and South Valley. Partly Sunny. 35/52 Tue (25 Nov): Chance of Light Rain. Snow Level 5000 Feet. 38/53 Wed (26 Nov): Areas of Am Fog. Partly Sunny. 35/50 Thu (27 Nov): Increasing Clouds and Indigestion. Chance of Light Rain Late. 35/48 Fri (28 Nov): Becoming Mostly Sunny. NE Winds. 34/49 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Mon Nov 24 08:59:29 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Mon, 24 Nov 2008 10:59:29 -0600 Subject: [willamette-fcst] Forecast - Monday, November 24th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Monday, November 24th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A strong upper-level ridge brought a return of dry weather over the weekend with a little sunshine...mainly in the north valley. By Sunday, low-level temperature inversions developed with poor ventialtaion conditions. Fog became locally persistent from about Aurora south to Eugene. Dry easterly outflow, from the Columbia Gorge, kept fog out of the north valley, near Portland. East winds guted to near 25 mph in the Portland area Sunday and to near 35 mph in Troutdale. There was considerable variation in temperatures across western Oregon Sunday. The foggy central and southern Willamette Valley stayed in the low to mid 40s, while the north valley and the coast saw a little sunshine and temperatures in the mid 50s. The upper-level ridge of high pressure will slowly shift east today but provide another day to Sunday across the state. The ODA surface analysis showed continued offshore gradients, and easterly winds were gusting over 30 mph at Troutdale, in the western Columbia Gorge. The east winds had relaxed in the Portland area, but the air was still too dry for fog formation north of about Wilsonville. Areas of dense fog covered the central and southern Willamette Valley. It was considerably colder this morning with surface temperatures in the valley near or slightly below freezing. Aurora and Mcinnville both dipped into the upper 20s and Salem dropped to 30 degrees. Easterly winds were keeing the coastline free of fog and holding temperatures mostly in the 40s. The morning sounding over Salem showed a strong low-level temperature inversion, from the surface to 2500 feet, where the temperature was in the low 50s. That will keep mixing heights at or below 500 feet today...making for poor ventilation conditions. A developing south-southwesterly flow aloft will increase the middle and high clouds across western Oregon today and tonight. Offshore flow, at the surface, is forecast to weaken slightly today, so fog will be persistent in the central and southern Willamette Valley, where high temperatures will stay mosly in the low to mid 40s. The north valley, near Portland, will continue to see enough dry easterly outflow, from the Gorge, to allow for partly sunny skies with temperatures climbing in the low to mid 50s. Surface Winds: SE 0-5 this morning, N 0-5 this afternoon. Transport Winds: Var 3 this morning, Var 3 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 500 feet. Ventilation index 2. High Temperature: Salem\'s high temperature today will be near 46. Humidities: Minimum relative humidity will be near 93%. Sunrise/Sunset: Salem sunset tonight: 4:36pm; sunrise tomorrow: 7:23am. Extended Outlook: The ridge is forecast to begin breaking down tomorrow with increasing southwesterly flow aloft. A split-flow pattern in the jet stream will likely take most of the punch out of a cold front, as it comes onshore tomorrow afternoon. It should be strong enough to bring some light rain to western Oregon and a little snow to the higher elevations in the Cascades. This system should be strong enough to stir the air and help warm surface temperatures to near 50 in the central and southern Willamatte Valley. Total rainfall amounts will likely be about one-tenth of an inch or less. A transitory ridge is forecast to bring back dry conditions Wednesday with a return of valley fog...mainly in the central and southern Willamette Valley. Increasing offshore flow will help the north valley see a little afternoon sunshine. The next weak weather system will bring a chance of a little rain on Thanksgiving. A strong upper-level ridge is forecast to build back over the region beginning Friday. That would bring a return of stagnant weather conditions. Increasing offshore flow will, once again, act to keep fog out of the north valley, but fog will likely become persistent in the central and south valley. Tue (25 Nov): Light Rain Likely Developing by the Afternoon. Snow Level 6000 Feet. 35/51 Wed (26 Nov): Areas of Am Fog. Partly Sunny...Mainly North. 34/51 Thu (27 Nov): Chance of Light Rain. 34/50 Fri (28 Nov): Areas of AM Fog. Partly Sunny. 34/50 Sat (29 Nov): Areas of Fog. Partly Sunny. 34/50 Sun (30 Nov): Areas of Fog. Partly Sunny. 34/50 Mon (01 Dec): Areas of Fog. Partly Sunny. 34/50 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Tue Nov 25 08:57:52 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Tue, 25 Nov 2008 10:57:52 -0600 Subject: [willamette-fcst] Forecast - Tuesday, November 25th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Tuesday, November 25th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: There was quite a range in high temperatures across western Oregon Monday afternoon with offshore flow warming the coastline to near 60 degrees. Parlty sunny skies allowed sections of the northern Willamette Valley to climb into the low 50s, while persisten fog in the central and south valley held temperatures in the 40s. Covallis only managed a high of 39 degrees. Areas of dense fog reformed over much of the Willamette Valley overnight, as a protective upper-level ridge of high pressure remained over the region. By early this morning, many Willamette Valley locations had, once again cooled to near or below the freezing mark. Hillsboro, McMinnville, and Salem all dropped to 30 degrees and Aurora matched the freezing mark. Increasing cluds helf south valley temperatures a little higher with Eugene bottoming out at 34 and Corvallis 36 degrees. The Salem sounding showed similar temperatures aloft, compared with Monday. A strong low-level temperature inversion was still present, with temperatures warming to 50 degrees by about 2500 feet and remaining warm through the 4500-foot level. The strong upper-level ridge is shifting eastward today and will allow a weakening cold front, in a split-flow jet-stream pattern, to come onshore. Satellite imagery showed middle and high clouds over the entire state and Doppler radar showed light rain had moved onto the central Oregon Coast and into sections of southwest Oregon. The rain was moving northeastward into the southern Willamette Valley. The approaching cold front, about 150 miles offshore, should be strong enough to bring light rain to all of western Oregon today, with a little snow falling in the higher elevations in the Cascades. The cold front was already beginning to lift the fog in the south valley, at mid-morning, and should help surface temperatures there warm a few degrees, compared to Monday. Afternoon temperatures will be more uniform across western Oregon with highs mostly in the mid and upper 40s. Valley rainfall totals will likely be about one-tenth of an inch or less. Poor ventilation conditons will continue today with warm air aloft leading to low mixing heights. Transport winds will be light and variable Surface Winds: SE 0-5 this morning, Var 2-6 this afternoon. Transport Winds: SW 3 this morning, Var 4 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 500 feet. Ventilation index 2. High Temperature: Salem\'s high temperature today will be near 47. Humidities: Minimum relative humidity will be near 79%. Sunrise/Sunset: Salem sunset tonight: 4:35pm; sunrise tomorrow: 7:25am. Extended Outlook: The light rain over western Oregon should taper off this evening, as the cold front moves onshore and falls apart. A transitory ridge is forecast to bring back dry conditions Wednesday with a return of valley fog...mainly in the central and southern Willamette Valley. Increasing offshore flow will help the north valley see a little afternoon sunshine, due to dry easterly outflow from the Columbia Gorge. The next weak weather system will also be very weak but possibly strong enough to bring a little rain late Thanksgiving day. A strong upper-level ridge is forecast to rebuild over the region, beginning Friday, with a continuation of stagnant weather conditions and areas of persistent valley fog. Increasing offshore flow will, once again, act to keep widespread fog out of the north valley, where temperatures will likely be a little warmer than in the foggy south valley. The next threat of precipitation does not appear to be until at least Tuesday of next week. Tomorrow (26 Nov): Areas of Am Fog. Partly Sunny...Mainly North. 34/51 Thu (27 Nov): Increasing Chance of Light Rain. 34/50 Fri (28 Nov): Areas of Fog. Partly Sunny in the Afternoon...Mainly North. 34/49 Sat (29 Nov): Areas of Fog. Partly Sunny in the Afternoon...Mainly North. 32/51 Sun (30 Nov): Areas of Fog. Partly Sunny in the Afternoon...Mainly North. 32/50 Mon (01 Dec): Areas of Fog. Partly Sunny in the Afternoon...Mainly North. 32/50 Tue (02 Dec): Mostly Cloudy. Slight Chance of Rain. 36/51 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Wed Nov 26 09:00:04 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Wed, 26 Nov 2008 11:00:04 -0600 Subject: [willamette-fcst] Forecast - Wednesday, November 26th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Wednesday, November 26th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A weak cold front managed to lift the dense fog from the Willamette Valley Tuesday but replaced it with a low overcast and light rain. Valley temperatures were chilly with highs only climbing into the low to mid 40s. Rainfall totals ranged from just a few hundredths of an inch, in the south valley, up to one-quarter of an inch in sections of the north valley. Only light precipitation fell in the Cascades, where the snow level stayed above about 6000 feet. The morning ODA surface analysis showed the cold front had moved east of the region and stretched from western Montana to the northeastern tip of Oregon. A stronger low pressure area was bringing rain to central and southern California. Dry conditions prevailed across Oregon with northerly surface gradients. There was some middle and high cloudiness circulating northward, over Oregon, from the California weather system. Visible satellite imagery showed considerable low clouds and areas of fog in the valleys of western and north-central Oregon. The Salem sounding this morning showed some cooling aloft since Tuesday, but not enough to break the low-level temperature inversion over the region. Mixing heights will be a little higher today than on Tuesday, but ventilation remains poor over the valley. Surface and transport winds were north-northeasterly. Northerly winds increased to about 10 mph acros most of the valley this morning, which kept temperatures from falling below the upper 30s. Light winds did allow hillsboro to drop to 31 degrees. A transitory ridge is forecast to maintain dry conditions today, although fog may be persistent...especially in the central and southern Willamette Valley. Increasing offshore flow will help the fog and low clouds clear from the north valley, with some afternoon sunshine. Valley highs should climb mostly into the low 50s, which is above normal for late November. Winds wind continue to increase slightly and turn more northeasterly this afternoon. Surface Winds: N 10 this morning, NE 10-15 this afternoon. Transport Winds: N 12 this morning, NE 14 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 2000 feet. Ventilation index 28. High Temperature: Salem\'s high temperature today will be near 52. Humidities: Minimum relative humidity will be near 59%. Sunrise/Sunset: Salem sunset tonight: 4:34pm; sunrise tomorrow: 7:26am. Extended Outlook: A splitting weather system will possibly be strong enough to bring a little rain to western Oregon late Thanksgiving day. A warm front will brush the northwest corner of Oregon with some clouds and a slight chance of light rain Friday. A strong upper-level ridge is forecast to rebuild over the region, beginning Friday night, with a continuation of stagnant weather conditions and areas of persistent valley fog. Increasing offshore flow will act to keep widespread fog out of the north valley Saturday and Sunday, but fog could become widespread and persistent in the central and southern valley. A weather system may flatten the ridge and bring a chance of rain as early as Monday of next week, but that is getting beyond the range of the computer models forecasts with this weather pattern. Tomorrow (27 Nov): Areas of AM Fog. Increasing Chance of Light Rain Late. 34/50 Fri (28 Nov): Areas of Fog. Mostly Cloudy. 37/49 Sat (29 Nov): Areas of Fog. Partly Sunny in the Afternoon...Mainly North. 33/51 Sun (30 Nov): Areas of Fog. Partly Sunny in the Afternoon...Mainly North. 33/51 Mon (01 Dec): Increasing Chance of Light Rain. 35/52 Tue (02 Dec): Areas of Fog. Partly Sunny...Mainly North. 33/49 Wed (03 Dec): Areas of Fog. Partly Sunny...Mainly North. 33/49 ODA Meteorologist weather at oda.state.or.us From willamette-fcst at listsmart.osl.state.or.us Fri Nov 28 09:00:59 2008 From: willamette-fcst at listsmart.osl.state.or.us (Willamette Valley Ag/Burning Forecast) Date: Fri, 28 Nov 2008 11:00:59 -0600 Subject: [willamette-fcst] Forecast - Friday, November 28th, 2008 Message-ID: Daily Smoke Management Forecast Oregon Department of Agriculture Smoke Management Program Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts. Issued: Friday, November 28th, 2008 at 9:00am. Burn Advisory: Agricultural burning is not recommended. Stack burning is not allowed. Weather Discussion: A splitting weather system was just strong enough to bring a little rain to western Oregon on Thanksgiving. Rainfall amounts along the coast ranged from one-third of an inch at Astoria to one-tenth of an inch at North Bend to just a trace at Brookings. The northern Willamette Valley received from a couple of hundredths to around one-tenth of an inch. Much of the south valley picked up only a trace of rain...including Corvallis and Eugene. Cloudy skies held afternoon temperatures in the low to mid 40s in the north valley, while the south valley warmed into the low 50s with some filtered sunshine. The upper-level ridge of high pressure that has been dominating the weather along the west coast for much of the second half of November is trying to rebuild over the region this morning. Widespread fog formed overnight across the Willamette Valley...locally reducing visibilities to one-quarter of a mile. A weak warm front was about 150 miles off the Washington Coast this morning. Light rain had spread into northwest Washington with satellite imagery showing clouds spreading across Washington and most of Oregon. Most of the rainfall from this system should stay north of Oregon, but there is a chance thta some drizzle or light rain could make it as far south as northwest Oregon...mainly this morning. The sounding over Salem showed warming aloft, associated with the approaching warm front, and a strengthening low-level temperature inversion. The freezing level had jumped to 10,000 feet and will continue to go up today. The ODA surface analysis showed weak southeastery gradients across western Oregon. The combination of light surface winds and low mixing heights will make for poor ventilation conditions, again, today over the valley. Skies were at mid-morning across western Oregon with areas of valley fog. Temperatures were in the low to mid 40s with light southeasterly winds. Clouds, fog, and local drizzle will give way to partial clearing this afternoon...mainly in the south valley. Temperatures will range from the mid to upper 40s in the north valley to the low 50s in the south valley this afternoon. Surface Winds: SE 0-5 this morning, SSE 0-5 this afternoon. Transport Winds: S 5 this morning, S 5 this afternoon. Atmospheric Ventilation Conditions: Maximum mixing height today will be near 500 feet. Ventilation index 3. High Temperature: Salem\'s high temperature today will be near 49. Humidities: Minimum relative humidity will be near 89%. Sunrise/Sunset: Salem sunset tonight: 4:33pm; sunrise tomorrow: 7:28am. Extended Outlook: A strong upper-level ridge is forecast to rebuild over the region Saturday and Sunday, with a continuation of stagnant weather conditions and areas of persistent valley fog. Increasing offshore flow will act to keep widespread fog out of the north valley, but fog could become widespread and persistent in the central and southern valley. Areas that break out of the fog could become unseasnoably mild in the afternoons, due to very warm air aloft. A weather system may flatten the ridge and bring a little rain to western Oregon Monday, with the greatest rainfall totals in the north valley. This system may bring enough cooling aloft and southerly winds to greatly improve ventilation conditions. The upper-level ridge is expected to rebuild over the region Tuesday for a return to more stagnant weather and areas of valley fog. The long-range computer models have varying solutions but are beginning to show a possible transition to a more westerly flow aloft, which could bring mild and wet weather to the region starting later next week. That would also improve ventilation conditions. Tomorrow (29 Nov): Areas of Fog. Partly Sunny in the Afternoon...Mainly North. 40/55 Sun (30 Nov): Areas of Fog. Partly Sunny in the Afternoon...Mainly North. 38/55 Mon (01 Dec): Chance of Light Rain. 38/54 Tue (02 Dec): Areas of Fog. Partly Sunny...Mainly North. 36/50 Wed (03 Dec): Areas of Fog. Partial Clearing. 35/50 Thu (04 Dec): Chance of Rain. 40/53 Fri (05 Dec): Chance of Rain. 40/53 ODA Meteorologist weather at oda.state.or.us