SMI South Central (Smoke Management Instructions) South Central Oregon Smoke Management Instructions

[ODF Smoke Management Instructions]

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS
SALEM FORESTRY WEATHER CENTER
OREGON DEPARTMENT OF FORESTRY

ISSUED: Tuesday, April 28, 2009       2:40 PM      Jim Little

1.  DISCUSSION AND FORECAST FOR SOUTH CENTRAL OREGON ZONES 624 AND 625

The upper low that brought clouds, rain and cool temperatures to the Pacific Northwest will track west to east across the state on Wednesday.  This will keep showers going thought the area.  The cool air aloft with this system will keep mixing heights high and smoke dispersal conditions should be good to excellent. Transport winds will generally be northwesterly through westerly.

    OUTLOOK (THURSDAY - SATURDAY):

On Thursday the upper low slowly pulls out to the east allowing weak ridging to build.  Mixing heights should remain high for good to excellent smoke dispersal conditions.  Transport winds will be easterly early, becoming northeasterly with time.  On Friday a Pacific system approaches Oregon from the southwest.  Computer models differ on the initial intensity of this system as it moves in.  Right now it looks like precipitation will spread across the southern Cascades during the day Friday.  Transport winds will be variable.  Precipitation continues Saturday with warm over-running ahead of a Pacific cold front that moves into western Oregon, and transport winds should be generally south through southwest.  While smoke dispersal conditions should be favorable during the afternoons, conditions may be too wet for effective burning.

2.  DISPERSION

WEDNESDAY
Mixing height above 5000 ft throughout the day.  Mixing height lowers to 2700 - 3700 ft during the evening.

Transport wind light and variable and controlled by local terrain during the morning.  Transport wind increases to WNW to NNW at 6 - 12 mph during the afternoon and increases to NNW to NNE at 10 - 18 mph during the evening.

Surface wind SW to W at 5 - 9 mph during the morning.  Surface wind shifts to W to NW and increases to 9 - 15 mph during the afternoon and evening.

OUTLOOK:

THURSDAY
Mixing height below 1000 ft early rising to 4100 - 5000 ft by late morning rising above 5000 ft during the afternoon.  Transport wind NE to E at 6 - 12 mph during the morning becoming E to SE at 5 - 9 mph during the afternoon.  Surface wind light and variable during the morning becoming SSW to WSW at 6 - 10 mph during the afternoon.

FRIDAY
Mixing height 2800 - 3800 ft during the morning rising above 5000 ft during the afternoon.  Transport wind light and variable.  Surface wind light and variable.

SATURDAY
Mixing height below 1000 ft early rising to 3200 - 4200 ft by late morning rising above 5000 ft during the afternoon.  Transport wind SE to SSW at 8 - 12 mph.  Surface wind SE to SSW at 6 - 12 mph.

3.  BURNING INSTRUCTIONS FOR ZONES 624 AND 625 INCLUDING THE WALKER
    RANGE PORTION OF ZONE 624
This instruction is valid for burning conducted on Wednesday, April 29, 2009.
==================================================================

Avoid ignitions within 10 miles to the W through NNE of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 15 miles to the W through NE in or near drainages leading to SSRAs.

==============================================================
4.  SPECIAL NOTE:

    The smoke management forecaster is available at (503)
    945-7401.  The smoke management forecaster is available
    to discuss specific burns.  The duty forecaster phone
    number is (503) 945-7401. Please call this number and
    not individual's numbers to discuss daily burning. Please
    avoid calling before 8 a.m. and between 2 to 3 p.m.

    This forecast is available on the Internet at:
      http://oregon.gov/ODF/FIRE/fire.shtml/#Smoke_Management

    Please ensure your units have been planned and accomplished by checking:
      http://oregon.gov/ODF/FIRE/SMP/dailysmoke.shtml


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://omls.oregon.gov/pipermail/smi_south_central/attachments/20090428/da592198/attachment.html>