[willamette-fcst] Forecast - Wednesday, February 10th, 2010
Willamette Valley Ag/Burning Forecast
willamette-fcst at listsmart.osl.state.or.us
Wed Feb 10 09:09:36 PST 2010
Daily Smoke Management Forecast
Oregon Department of Agriculture
Smoke Management Program
Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts.
Wednesday, February 10th, 2010 at 9:00am.
Recommended burn times for agricultural burning are from 12:00pm to 3:30pm.
Straw stack burning is allowed from 12:00pm until 3:30pm.
...The rules for stack burning have changed. Stack burning
permits must be obtained from ODA Smoke Management Personnel...
A drying northwesterly flow aloft helped to clear the low
clouds from the Willamette Valley late Tuesday afternoon.
Clearing skies allowed temperatures to drop to the freezing
mark in the Willamette Valley overnight, with areas of fog
reforming. Aurora was one of the colder spots with a low of
30 dgrees. Salem and McMinnville both dipped to 32. By
early this morning, however, clouds began to increase, from
an approaching storm system, with the fog lifting and
temperatures climbing into the upper 30s and lower 40s.
Satelite imagery showed a solid band of low clouds moving
onshore at mid-morning, with middle and high clouds
extending across the Cascades over much of central and
eastern Oregon. Doppler radar showed light precipitation
along the coast and extending into the central and southern
Willamette Valley. The ODA surface analysis showed
increasing southeasterly pressure gradients, with winds in
the 5-15 mph range greatly improving ventilation conditions
across western Oregon. Light rain was being reported at
Astoria and should spread across the Willamette Valley
during the next couple of hours.
Cloudy skies and occasional light rain will keep high
temperatures in the mid to upper 40s across the Willamette
Valley today, with low 50s possible along the coast.
Southeasterly winds will continue to increase slightly and
turn more southerly this afternoon, making for good
ventilation conditions over the valley. The freezing level
was measured at just over 5000 feet this morning, so snow
levels will be near the Cascade passes today, where a couple
of inches of new snow are possible. The frontal system is
forecast to stall over western Oregon today and become
activated by an approaching warm front tonight. That will
likely lift snow levels above the Cascade passes by Thursday
morning, with increasing rain across western Oregon.
SE 7-15 this morning, S 10-20 this afternoon.
S 15 this morning, SSW 20 this afternoon.
Atmospheric Ventilation Conditions:
Maximum mixing height today will be near 2500 feet. Ventilation index 50.
Salem\'s high temperature today will be near 47.
Minimum relative humidity will be near 74%.
Salem sunset tonight: 5:33pm; sunrise tomorrow: 7:19am.
Thursday should be quite wet and mild across western Oregon,
with a morning warm front followed by a fairly strong cold
front Thursday evening. Southerly winds will increase late
Thursday, with possible gusts to around 60 mph along the
coast Thursday night. The cold front should drop snow
levels back to the Cascade passes by Friday morning, as the
steady rain turns showery and begins to taper off.
A colder weather system is forecast to spread more rain
onshore Friday, with the snow level staying near or slightly
below the Cascade passes. Southeasterly winds should make
for good ventilation conditions. A transitory ridge of high
pressure may dry things out Saturday, especially south, as a
warm front brushes by to our north. It there is enough
mixing of the air mass, temperatures could become quite mild
Saturday afternoon. A weak cold front may bring some light
rain Sunday, with snow levels likely remaining near or above
the Cascade passes. Another warm front will bring a chance
of rain Monday, with snow levels lifting above the Cascade
passes. A weak cold front is forecast to come onshore Tuesday.
Thu (11 Feb): Rain Likely. Blustery Along the Coast Late. Snow Level 5500 Feet. 42/53
Fri (12 Feb): Rain Likely...Turning to Showers. Snow Level Dropping to 4000 Feet. 40/52
Sat (13 Feb): Chance of Light Rain...Mainly North. Mild. Snow Level 6000 Feet. 40/58
Sun (14 Feb): Mostly Cloudy and Mild. Chance of Light Rain. Snow Level 5500 Feet. 41/53
Mon (15 Feb): Chance of Light Rain...Mainly North. Snow Level 6000 Feet. 39/54
Tue (16 Feb): Chance of Rain. Snow Level 5000 Feet. 37/54
Wed (17 Feb): Partly Sunny. 36/57
weather at oda.state.or.us
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