[willamette-fcst] Forecast - Wednesday, January 7th, 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: 
     Wednesday, January 7th, 2009 at 9:00am.

Burn Advisory:
     Agricultural burning is allowed.  Suggested burn times are from now until 3:00pm.
     Straw stack burning is allowed from now until 3:00pm.

Weather Discussion:
     A very moist warm front was bringing heavy rain to western
     Washington and extreme northwestern Oregon this morning,
     along with strong southerly winds.  Rain and wind will
     continue to increase across western Oregon today, as the
     frontal boundary sags southward.  High wind warnings have
     been issued for the northern and central coast, and the
     northern coast range, for southerly gusts between 60 and 70
     mph.  Southerly winds in the Willamette Valley will gust to
     between 30 and 40 mph with increasing rain.

     The freezing levels over Oregon are near 10,000 feet.  Flood
     watches have been issued western Oregon due to melting snow
     and increasing rain. The latest flood advisories can be
     accessed at: http://www.wrh.noaa.gov/pqr/

Surface Winds:
     S 15-25 G 35 this morning, S 15-25 G 35 this afternoon.
Transport Winds:
     SSW 35 this morning, SSW  40 this afternoon.
Atmospheric Ventilation Conditions:
     Maximum mixing height today will be near 2500 feet.  Ventilation index 88.
High Temperature:
     Salem\'s high temperature today will be near 54.
Humidities:
     Minimum relative humidity will be near 89%.
Sunrise/Sunset:
     Salem sunset tonight: -1:20pm; sunrise tomorrow: : 0am.

Extended Outlook:
     A strong cold front will move onshore early Thursday morning
     with locally heavy rain and strong winds continuing.  South
     winds could gust to around 60 mph along the coastal
     headlands and beaches, and to near 70 mph in the northern
     coastal range, until the cold front pushes east.  Southerly
     winds will continue to gust to near 40 mph in the Willamette
     Valley through early Thursday.  Cooler air aloft will drop
     the snow level to near 3000 feet by Thursday evening with
     the precipitation becoming more showery and focused mainly
     on the western slopes of the coast range and Cascades.

     Showers will taper off Thursday night, as an upper-level
     ridge of high pressure begins building over the region. 
     Cooler overnight temperatures and moist low-level air will
     likely lead to areas of fog in the western valleys by Friday
     morning.  Freezing levels will jump back above the Cascade
     passes, but dry weather should help river levels drop and
     ease flooding concerns.

     The upper-level ridge will initially be rather flat. 
     Western flow aloft will allow another Pacific storm to slide
     into western Washington Saturday.  Some rain could make it
     south into northwestern Oregon late in the day.  The
     upper-level ridge is forecast to amplify Sunday with the
     flow aloft becoming northwesterly and drying out.  The ridge
     is forecast to move over the region early next week with dry
     weather expected and freezing levels rising to more than
     10,000 feet.  Ventilation conditions will become 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 Monday through Wednesday.

Thu (08 Jan):  Rain and Windy...Turning to Showers.  Snow Level Dropping to 3000 Feet.  48/50

Fri (09 Jan):  Areas of AM Fog.  Becoming Partly Sunny.  34/46

Sat (10 Jan):  Areas AM Fog.  Mostly Cloudy.  Increasing Chance of Light Rain North.  32/46

Sun (11 Jan):  Areas of AM Fog.  Partial Clearing.  34/48

Mon (12 Jan):  Areas of AM Fog.  Partly Sunny.  33/50

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

ODA Meteorologist
weather at oda.state.or.us