[willamette-fcst] Forecast - Tuesday, April 22nd, 2008
Willamette Valley Ag/Burning Forecast
willamette-fcst at listsmart.osl.state.or.us
Tue Apr 22 11:10:53 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.
...Next Update 9 am Wednesday, April 23, 2008...
Tuesday, April 22nd, 2008 at 12:00pm.
Agricultural burning is allowed. Suggested burn times are from now until 6:00pm.
Straw stack burning is allowed from now until 6:00pm.
The showers from Monday changed to a steady rain across
Western Oregon overnight in response to a potent warm front
from a surface low pressure area approaching the Central
Oregon Coast. Offshore flow kept cool air in place across
Northern Oregon with snow levels remaining near 1500 feet
overnight, while warming aloft lifted snow levels to near
4000 feet over Southern Oregon by early this morning.
The clouds and rain kept valley temperatures from dropping
below about 40 degrees overnight, even though the air aloft
remained unseasonably cold. Total rainfall amounts in the
24 hours ending at 5 am today ranged from around one-tenth
to one-third of an inch in the Willamette Valley with just
under one-half inch falling along the Oregon Coast. Up to a
tenth of an inch of additional rain fell across the region
between 5 am and 11 am this morning.
This is a very cold storm that would have produced
widespread snow over Western Oregon, had this pattern set up
during the winter season. It did produce snow overnight in
the northern coastal range and in the Cascades above about
1500 feet. The Cascade Passes remained mostly snow-packed
late this morning with temperatures in the 30s.
Clouds had penetrated inland across the Cascades and Central
Oregon by late this morning with some light rain reported in
Redmond. Warmer air had pushed Central Oregon temperatures
into the upper 40s with snow levels jumping above 4000 feet.
The eastern third of the state was seeing sunshine at midday
with temperatures ranging from the upper 40s to mid 50s.
The ODA surface analysis continued to show a low pressure
center west of Newport, but a second area of low pressure is
forming off the Southern Oregon Coast, along the surface
cold front offshore. A weak warm front extended from the
low-pressure center west to Newport to the Northern Oregon
Coast. To the north of the warm front, winds are
northeasterly at 5-15 mph across Western Washington and
portions of Northwestern Oregon. On the south side of the
warm front, southeasterly winds of 5-15 were blowing along
the Oregon Coast and south of about Eugene in the western
interior. The developing low pressure ara off the south
coast is keeping the surface flow northeasterly over NW
Oregon. Temperatures across Western Oregon were in the mid
to upper 40s with areas of rain increasing from south to north.
The warm front is forecast to weaken and slowly progress
northward today with rain at times continuing and
southeasterly winds migrating slowly northward across
Western Oregon. The warmer air aloft over Southern Oregon
will filter northward this afternoon with the snow level
over Northern Oregon creeping up to around 3000 feet. The
snow level over Southern Oregon will stay near 4000 feet.
Clouds and rain will help hold valley temperatures in the
low 50s (about 10 degrees below average).
NE 5-15 mph north valley...SE 5-15 south valley this afternoon.
S 20-25 this afternoon.
Atmospheric Ventilation Conditions:
Maximum mixing height today will be near 4000 feet. Ventilation index 100.
Salem\'s high temperature today will be near 52.
Minimum relative humidity will be near 69%.
Salem sunset tonight: 8:07pm; sunrise tomorrow: 6:13am.
The cold front from the slow-moving offshore storm system
will finally move inland tonight. The associated cold
upper-level trough will move over the region Wednesday and
Thursday for showers and a return of quite low snow levels.
High pressure will build into the coastline Friday and begin
to dry out the air mass. That may lead to cool temperatures
over sections of the valley Friday and/or Saturday mornings
with daytime temperatures shooting above normal Saturday.
The next weather system is forecast to move onshore Sunday
night and Monday.
Tomorrow (23 Apr): Showers. Chance T-Storm. Snow Level Dropping to 1500 Feet. 42/52
Thu (24 Apr): Mostly Cloudy. Chance of Showers. Snow Level Rising to 3000 Feet. 37/56
Fri (25 Apr): Mostly Cloudy. Decreasing Chance of Showers. Snow Level 4000 Feet. 36/58
Sat (26 Apr): Becoming Mostly Sunny and Warmer. 34/67
Sun (27 Apr): Increasing Clouds. Rain Likely Late. 40/63
Mon (28 Apr): Rain Likely and Cooler. 44/58
Tue (29 Apr): Showers. Snow Level 2500 Feet. 40/55
weather at oda.state.or.us
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