[willamette-fcst] Forecast - Tuesday, September 15th, 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: 
     Tuesday, September 15th, 2009 at 9:00am.

Burn Advisory:
     Agricultural burning is allowed.  Suggested burn times are from 2:00pm until 5:00pm.
     Preparatory burning is not allowed.
     Propane flaming is allowed from 2:00pm until 5:00pm.
     Straw stack burning is allowed from 2:00pm until 5:00pm.

Weather Discussion:
     An upper-level ridge of high pressure will build over the
     region today, bringing mostly sunny skies and warm
     temperatures to the Willamette Valley. Satellite imagery
     showed a band of clouds, moving northward, from the north
     coast across much of the Willamette Valley.  Skies were
     mostly sunny in it\'s wake.  The air aloft was still quite
     cool this morning but will warm during the day, helping
     temperatures climb into the mid 80s this afternoon. Forecast
     southeasterly transport winds may allow for the burning of
     western valley fields around midday.

Surface Winds:
     Var 0-5 this morning, SSE 5-10 this afternoon.
Transport Winds:
     SSE 6 this morning, SSW 10 this afternoon.
Atmospheric Ventilation Conditions:
     Maximum mixing height today will be near 4000 feet.  Ventilation index 40.
High Temperature:
     Salem\'s high temperature today will be near 84.
Humidities:
     Relative humidity drops to 50% by 12pm.
     Minimum relative humidity will be near 33%.
Sunrise/Sunset:
     Salem sunset tonight: 7:22pm; sunrise tomorrow: 6:52am.

Extended Outlook:
     The upper-level ridge is forecast shift east of the region
     Wednesday with increasing southerly flow aloft.  A cold
     front is forecast to move onshore Wednesday afternoon. 
     Depending on the timing of cold front, it could create a
     burning opportunity, for remaining central and eastern
     valley fields, Wednesday afternoon.  Some light rain is
     likely over much of the Willamette Valley by Wednesday
     evening...especially north.  Total rainfall amounts are
     forecast to be around one-tenth of an inch or less with the
     rain quickly tapering off Thursday morning.

     Some clearing is likely by Thursday afternoon with
     near-normal temperatures.  A very weak and transitory ridge
     will warm temperatures a few degrees Friday.  Another weak
     cold front is forecast to come onshore Friday night and
     Saturday, with most of the rain staying north of the state. 
     Some very light rain is possible, mainly in the north
     valley, Saturday morning, with skies beginning to clear by
     Saturday evening.

     All of the long-range computer models are showing a strong
     upper-level ridge building over the west coast, beginning
     Sunday, with offshore flow, sunshine, and quite warm
     temperatures on tap for much of next week.

Tomorrow (16 Sep):  Becoming Mostly Cloudy.  Increasing Chance of Rain PM.  55/78

Thu (17 Sep):  Mostly Cloudy AM...Afternoon Clearing.  55/77

Fri (18 Sep):  Mostly Sunny.  Increasing Clouds Late.  51/81

Sat (19 Sep):  Chance of AM Rain...Mainly North.  Clearing by Evening.  54/75

Sun (20 Sep):  Sunny and Warmer.  50/83

Mon (21 Sep):  Sunny and Very Warm.  54/90

Tue (22 Sep):  Sunny and Very Warm.  54/90

ODA Meteorologist
weather at oda.state.or.us