[willamette-fcst] Forecast - Friday, August 1st, 2008
Willamette Valley Ag/Burning Forecast
willamette-fcst at listsmart.osl.state.or.us
Fri Aug 1 08:02:32 PDT 2008
Daily Smoke Management Forecast
Oregon Department of Agriculture
Smoke Management Program
Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts.
Friday, August 1st, 2008 at 9:00am.
Agricultural burning is allowed. Suggested burn times are from 2:00pm until 7:00pm.
Preparatory burning is allowed from 2:00pm until 5:00pm with a 100 acre limit.
Propane flaming is allowed from 2:00pm until 5:00pm.
Straw stack burning is allowed from 2:00pm until 7:00pm.
A weakening cold front was moving onto the Northern Oregon
Coastline this morning and will likely stall over the
Willamette Valley this afternoon. The front dumped up to
one-half of an inch of rain along the Northern Washington
Coast, since yesterday morning, with one-tenth to one-third
of an inch falling in the northern interior of Western Washington.
The front is drying out as it slowly moves southward with
only spotty light rain expected today across NW Oregon. The
north valley could see a few hundredths of an inch of rain,
with only a chance of showers in the south valley. Some
light rain was reported this morning along the Northern and
Central Oregon Coast and in the extreme Northern Willamette
Valley. Aurora picked up .01 inches with trace amounts as
far south as Salem.
The Salem sounding this morning showed cooling aloft, so
mixing heights will likely reach 3000 feet later this
afternoon, even with much cooler temperatures today. Cloudy
skies should hold valley highs in the low 70s (about 10
degrees cooler than Thursday). Open burning is unlikely today
due to marginal mixing heights and gradient-stacking issues.
Ahead of the cold front, surface winds across the valley
were southerly this morning at about 5-10 mph. Transport
winds were southwesterly this morning and are expected to
turn more westerly this afternoon, which is favorable for
valley ventilation. Therefore, propane and prep burning is
allowed later today. Some fields may get light rain between
now and when burning is allowed this afternoon. Please note
that burning is allowed only for fields that stay dry.
S 5-10 this morning, W 5-10 this afternoon.
SW 12 this morning, WSW 12 this afternoon.
Atmospheric Ventilation Conditions:
Maximum mixing height today will be near 3500 feet. Ventilation index 42.
Salem\'s high temperature today will be near 72.
Minimum relative humidity will be near 51%.
Salem sunset tonight: 8:38pm; sunrise tomorrow: 5:59am.
An upper-level trough will swing onshore this evening, in
the wake of the cold front. Strong onshore flow will keep
skies mostly cloudy tonight through much of Saturday. The
trough will slowly weaken over the weekend, with onshore
flow becoming more northerly and temperatures recoving to
near normal by Sunday.
A ridge of high pressure is forecast to build over the
Pacific Northwest early next week. The low-level winds will
turn north-northeasterly with valley temperatures possibly
warming to near 90 degrees. Increasing south to
southwesterly flow aloft is forecast for the second half of
next week with an increased threat of thundershowers...mainly
from the Cascades eastward. Increasing onshore flow may
create a burn opportunity during the second half of next week,
if the flow aloft is not too southerly.
Tomorrow (02 Aug): Morning Clouds...Afternoon Clearing. 53/76
Sun (03 Aug): Patchy Morning Clouds...Sunny and Warmer in the Afternoon. 49/82
Mon (04 Aug): Sunny and Warm. 52/85
Tue (05 Aug): Mostly Sunny and Very Warm. 54/90
Wed (06 Aug): Partly Cloudy. Slight Chance of T-Storms Near the Cascades. 54/89
Thu (07 Aug): Partly Cloudy and Cooler. Slight Chance Showers/T-Storms. 56/84
Fri (08 Aug): Partly Cloudy. Slight Chance of a Shower. 55/84
weather at oda.state.or.us
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