[willamette-fcst] Forecast - Wednesday, October 14th, 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.

...There will be no noon update today...

Issued: 
     Wednesday, October 14th, 2009 at 9:00am.

Burn Advisory:
     Agricultural burning is allowed.  Suggested burn times are from now until 4:30pm.
     Straw stack burning is allowed, for dry stacks, from 11:00am until 4:30pm.

Weather Discussion:
     A strong low-pressure center was moving north, about 150
     miles off the northern Washington Coast, at mid-morning.  An
     associated frontal system brought dumped from one-quarter to
     about one-half inch of rain across the Willamette Valley
     overnight and was moving into central Oregon at mid-morning.

     Strong southerly pressure gradients were bringing brisk
     southerly winds to most of western Oregon.  The strongest
     winds were along the coast and in the coastal range.  South
     winds gusted to 60 mph along the central Oregon Coast
     earlier this morning, in the Newport area, with gusts in
     excess of 40 mph extending northward to Astoria.  Mt Hebo,
     in the north coast range, recorded gusts to 68 mph.  Winds
     were still gusting to between 40 and 50 mph from the coast
     to the coast range at mid-morning.

     Southerly winds were not as strong in the Willamette Valley
     this morning, but gusts between 20 and 30 mph were common. 
     The southerly winds were helping scour the cold air from the
     Willamette Valley, with mid morning temperatures generally
     as warm as Tuesday\'s highs (mid 50s).  Easterly outflow,
     from the Columbia Gorge, is keeping the immediate Portland
     area in the upper 40s and low 50s.

     Satellite imagery and Doppler Radar showed the main
     rain-bands moving well east of the valley and into central
     Oregon, where temperatures finally have warmed above
     freezing.  After getting freezing rain, off and on during
     the day Tuesday, Redmond finally picked up a southerly wind
     this morning, around 5am, and their temperature jumped from
     near freezing into the mid 40s, with plain old rain.  The
     southerly winds and bands of rain will progress eastward
     across Oregon today, along with moderating temperatures.

     A strong onshore flow will continue to circulate clouds and
     showers inland across western Oregon today, along with some
     sunbreaks.  After hitting highs only in the mid 50s Tuesday,
     warming southerly winds will help Willamette Valley temperatures
     climb into the low 60s this afternoon.  Amazingly, snow fell in
     the Columbia Gorge Tuesday...possibly the earliest snowfall on
     record for some locations.  Who knows what that means for this
     winter, but October, 2009 has seen some rare weather events.

Surface Winds:
     S 10-20 G30 this morning, SSW 7-15 G25 this afternoon.
Transport Winds:
     SSW 30 this morning, SSW 30 this afternoon.
Atmospheric Ventilation Conditions:
     Maximum mixing height today will be near 3000 feet.  Ventilation index 90.
High Temperature:
     Salem\'s high temperature today will be near 61.
Humidities:
     Minimum relative humidity will be near 60%.
Sunrise/Sunset:
     Salem sunset tonight: 6:28pm; sunrise tomorrow: 7:28am.

Extended Outlook:
     A warm front will likely bring some light rain to mainly
     northwestern Oregon Thursday, with the snow level lifting
     above 8000 feet in the Cascades. A transitory ridge will
     bring brief drying and warming late Thursday and Friday.  A
     cold front is forecast to swing onshore Friday evening. 
     Southwesterly flow aloft will direct the bulk of the rain
     from that system into southern British Columbia and Western
     Washington, but the entire Willamette Valley should pick up
     at least some rain.

     A few showers could linger into Sunday with yet another
     weather system forecast to come onshore Sunday night and
     Monday.  It appears as if a transitory ridge may bring some
     drying and warming next Tuesday and Wednesday.

Tomorrow (15 Oct):  Mostly Cloudy.  Light Rain Likely North...Chance of Rain South. 51/65

Fri (16 Oct):  Mostly Cloudy but Warmer.  Chance of Rain Late.  50/70

Sat (17 Oct):  Rain Turning to Showers.  53/63

Sun (18 Oct):  Mostly Cloudy.  Chance of Showers.  Increasing Rain Late.  47/62

Mon (19 Oct):  Rain Turning to Showers.  49/60

Tue (20 Oct):  Areas of AM Fog...Becoming Partly Sunny.  45/66

Wed (21 Oct):  Areas of AM Fog.  Partly Sunny.  Increasing Clouds Late.  44/66

ODA Meteorologist
weather at oda.state.or.us