[willamette-fcst] Forecast - Friday, July 20th, 2007
Willamette Valley Ag/Burning Forecast
willamette-fcst at listsmart.osl.state.or.us
Fri Jul 20 12:01:32 PDT 2007
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, July 20th, 2007 at 12:00pm.
Agricultural burning is not recommended.
Preparatory burning is not allowed.
Propane flaming is not allowed.
Stack burning is not allowed.
A southwesterly flow aloft is steering a very moist weather
system into the Pacific Coastline this morning. Light rain
has been falling most of the morning along the northern coastal
strip, with Astoria receiving just over a tenth of an inch (.13\").
Very light rain has been falling off and on in the Northern
Willamette Valley, with amounts ranging from a trace in Salem to
three-hundredths (.03\") of an inch in Hillsboro.
At midday, doppler radar was showing rain across the NW corner of the
state, with the back edge just north and west of Salem. More areas of
rain will be circulating into Western Oregon this afternoon and evening,
as the whole weather pattern slowly shifts eastward.
Predicting rainfall amounts from this system is tricky, because Western
Oregon is getting a glancing blow for this very moist storm. Most of the
rain will fall along the North Oregon Coast and across Western Washington,
but the Willamette Valley could get a tenth to a quarter of an inch by Saturday
morning. The greatest amounts will be in the northern valley.
Some warming aloft has decreased mixing heights today, but
burning advisory decisions were based on the need for
another drying day, more light rain forecast for this
afternoon, and south-southwesterly transport winds.
Southwesterly surface winds will increase this afternoon, in
the Willamette Valley, as a cold front approaches the Oregon
SSW 13 this afternoon.
SSW 20 this afternoon.
Atmospheric Ventilation Conditions:
Maximum mixing height today will be near 4000 feet. Ventilation index 80.
Salem\'s high temperature today will be near 72.
Minimum relative humidity will be near 55%.
Salem sunset tonight: 8:52pm; sunrise tomorrow: 5:46am.
A damp weekend is in store, as a southwesterly flow aloft
steers a couple of very moist weather systems up the Pacific
Coastline. The first system, which will bring rain into the
Willamette Valley This afternoon and evening, will move into
the valley and weaken Saturday, and the second system is
forecast to approach the coastline Sunday morning.
Sunday\'s system not expected to push as far east, with the
valley likely receiving less than a tenth of an inch of
rain. It will weaken considerably, as it moves inland
Monday. By Monday night, an upper level ridge of high
pressure will build enough over the Pacific Northwest to
weaken the storm track. That will bring some drying and
warming, but no prolonged dry or hot weather is forecast.
Tomorrow (21 Jul): Light Rain Likely at Times. 59/75
Sun (22 Jul): Light Rain Likely at Times. 60/77
Mon (23 Jul): Mostly Cloudy. Chance of Showers. 60/78
Tue (24 Jul): Partly Sunny. 56/80
Wed (25 Jul): Mostly Cloudy. Slight Chance of Showers. 57/75
Thu (26 Jul): Morning Clouds...Afternoon Sun. 57/80
Fri (27 Jul): Mostly Sunny. 55/83
weather at oda.state.or.us
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