[willamette-fcst] Forecast - Friday, January 9th, 2009

[Willamette Valley Ag/Burning Forecast]

Daily Smoke Management Forecast




Oregon Department of Agriculture
Smoke Management Program
Weather Outlook and Field Burning Advisory for Willamette Valley Growers and Fire Districts.

Issued: 
     Friday, January 9th, 2009 at 9:00am.

Burn Advisory:
     Agricultural burning is not recommended.
     Stack burning is not allowed.

Weather Discussion:
     Many rivers in western Washington are still flooding today,
     due to recent heavy rain and melting snow.  Most rivers in
     northwest Oregon have crested and are now below flood stage.
     However, flood warmings remain in effect for the Luckiamute
     and Nehamlem Rivers, which were still above flood stage this
     morning.  The Luckiamute River, near Suver, is forecast to
     drop below flood stage this morning, with some low lying and
     agricultural flooding expected in Benton and Polk Counties. 
     The Nehalem River, near Foss, is expected to stay above
     flood stage until tonight, with some minor flooding
     continuing in Clatsop and Tillamook Counties.  

     The latest flood warnings can be accessed at:
     http://www.wrh.noaa.gov/pqr/

     The latest river levels and forecasts are at:
     http://ahps2.wrh.noaa.gov/ahps2/index.php?wfo=pqr

     The strong Pacific storm that brought heavy rain and strong
     winds to western Washington and northwestern Oregon, Tuesday
     and Wednesday, pushed east of the region yesterday with
     showers tapering off overnight.  Lowering snow levels and
     drier conditions have helped ease the flooding across the
     region.  Significant flooding is still occuring near
     Chehalis, Washington, where northbound Interstate 5 remained
     closed this morning due to high water.

     The latest Oregon road conditions are at:
     http://167.131.0.179/Pages/RCmap.asp?curRegion=0&mainNav=RoadConditions

     Cooler air aloft dropped the freezing level to just 2700
     feet over Salem this morning.  Partial clearing overnight
     helped Willamette Valley temperatures drop to near 30
     degrees with areas of fog forming...mainly in the central
     and south valley. Eugene fell to an icy 29 degrees this
     morning with fog reducing visibilities to less than
     one-quarter of a mile.

     The ODA surface analysis showed high pressure over western
     Oregon with weak pressure gradients and very light winds. 
     Warming aloft today will trap cool and moist air near the
     surface, so fog will have a tough time breaking up in
     portions of the central and south valley.  Afternoon highs
     today will range from near 40, in foggy areas, to the mid
     40s where the sun is able to make an appearance. 
     Ventilation conditions will be poor, dur to increasing
     low-level temperature inversions and light transport winds.

Surface Winds:
     Var 0-5 this morning, Var 0-5 this afternoon.
Transport Winds:
     SE 4 this morning, SE 4 this afternoon.
Atmospheric Ventilation Conditions:
     Maximum mixing height today will be near 1000 feet.  Ventilation index 4.
High Temperature:
     Salem\'s high temperature today will be near 43.
Humidities:
     Minimum relative humidity will be near 73%.
Sunrise/Sunset:
     Salem sunset tonight: 4:50pm; sunrise tomorrow: 7:49am.

Extended Outlook:
     Westerly flow aloft will allow another Pacific storm to
     slide into western Washington Saturday.  Some light rain
     could make it south into northwestern Oregon late by in the
     day...continuing into Sunday.  An upper-level ridge is
     forecast to amplify, just off the coastline, Sunday with the
     flow aloft becoming northwesterly and drying out by Sunday night.

     The ridge is forecast to move over the region next week with
     dry weather and freezing levels rising to more than 10,000
     feet.  Ventilation conditions will continue to be stagnant.
     Some easterly outflow from the Columbia Gorge will help to
     clear skies in the north valley, but the south valley may
     have fairly persistent fog much of next week.

Sat (10 Jan):  Areas AM Fog.  Mostly Cloudy.  Increasing Chance of Light Rain North.  30/45

Sun (11 Jan):  Mostly Cloudy.  Chance of Sprinkles North.  34/48

Mon (12 Jan):  Areas of AM Fog.  Partly Sunny.  35/50

Tue (13 Jan):  Areas of AM Fog...Mainly South.  Partly Sunny.  34/51

Wed (14 Jan):  Areas of AM Fog...Mainly South.  Partly Sunny.  34/51

Thu (15 Jan):  Areas of AM Fog...Mainly South.  Partly Sunny.  34/51

Fri (16 Jan):  Areas of AM Fog...Mainly South.  Partly Sunny.  34/51

ODA Meteorologist
weather at oda.state.or.us