[willamette-fcst] Forecast - Thursday, February 11th, 2010
Willamette Valley Ag/Burning Forecast
willamette-fcst at listsmart.osl.state.or.us
Thu Feb 11 09:10:11 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.
Thursday, February 11th, 2010 at 9:00am.
Recommended burn times for agricultural burning are from now to 3:30pm.
Straw stack burning is allowed from now until 3:30pm.
...The rules for stack burning have changed. Stack burning permits must
be obtained from ODA Smoke Management Personnel...
A weakening frontal system spread mostly light rain across
western Oregon Wednesday, before stalling over the region.
Increasing southerly winds, ahead of an approaching warm
front, led to midnight maximum temperatures across much of
western Oregon Wednesday night. Willamette Valley readings
climbed into the upper 40s by midnight, with some areas
continuing to warm into the low 50s early this morning.
Satellite imagery showed a rather complex-looking cloud
pattern extending from over Washington and Oregon to more
than 400 miles offshore. The fairly moist Pacific storm
system was beginning to split apart, under the split-flow
jet stream pattern just off the west coast. A surface low
pressure center appeared to be developing about 450 miles
off the southern Oregon/northern California coastline, with
a warm front advancing out ahead of it towards Washington
Skies were cloudy across all of Oregon with Doppler radar
showing areas of light rain and higher elevation snow
sweeping from west to east across the state. Between
one-half and three-quarters of an inch of rain have fallen
along the coast in the past 24 hours. In contrast, inland
precipitation amounts have been mostly light. Western
valleys have only received about one-tenth to one-quarter of
an inch, with areas east of the Cascades generally picking
up less than one-tenth of an inch. Snow levels are on the
rise and had climbed just above the Cascade passes by mid-morning.
The offshore low pressure system is forecast to track close
enough to the coastline later today to bring strong
southerly winds to much of the Oregon Coast. The National
Weather Service has issued high wind warnings for the Oregon
Coast, for southerly gusts up to 70 mph, late this afternoon
through this evening. Southerly winds will also increase
today in the Willamette Valley, with gusts of 35-40 mph
possible by this evening. Rain will also be on the increase
today, with snow levels likely staying above the passes. It
will be very mild, with southerly winds helping lift
temperatures into the mid 50s.
SSE 10-20 G25 this morning, SSE 12-25 G35 Late this afternoon.
S 25 this morning, S 35 this afternoon.
Atmospheric Ventilation Conditions:
Maximum mixing height today will be near 2500 feet. Ventilation index 88.
Salem\'s high temperature today will be near 55.
Minimum relative humidity will be near 69%.
Salem sunset tonight: 5:35pm; sunrise tomorrow: 7:17am.
The cold front asociated with the offshore weather system
will finally come onshore overnight...dropping the snow
level to the Cascade passes. 3-6 inches of snow are
possible, at pass level, before the precipitation tapers off
Friday morning. The brisk southerly winds across western
Oregon will rapidly taper off overnight, in the wake of the
frontal passage, with the steady rain turning showery and
A colder weather system is forecast to spread more rain
onshore around midday Friday. The snow level will likely
stay near or slightly below the Cascade passes.
Southeasterly winds will not be as brisk with this system
but should provide good ventilation conditions.
A transitory ridge of high pressure should dry things out
Saturday, especially south, as a warm front brushes by to
our north. Afternoon temperatures could become quite mild
Saturday with some sunbreaks possible. A weak cold front
will likely bring some light rain Sunday, with snow levels
likely remaining above the Cascade passes. Another warm
front will bring a chance of rain Monday, with a weak cold
front coming onshore Tuesday. Next Wednesday and Thursday
look dry & very mild, with increasing offshore flow, as a strong
upper level ridge of high pressure builds over the west coast.
Fri (12 Feb): Increasing Rain in the Afternoon. Snow Level Dropping to 4000 Feet. 46/54
Sat (13 Feb): Chance of Light North. Mostly Cloudy South. Snow Level 6000 Feet. 44/58
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): Areas of AM Fog. Becoming Partly Sunny & Mild in the Afternoon. 36/57
Thu (18 Feb): Mostly Sunny and Spring-Like. 38/62
weather at oda.state.or.us
More information about the willamette-fcst