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, May 12, 2009       2:40 PM      Jim Little

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

A weak upper trough moves east on Wednesday and weak high pressure aloft will build.  A Pacific front moving into western Oregon later Wednesday will spread moisture across the Cascades overnight Wednesday.  Mixing heights should remain favorable for good smoke dispersal conditions and transport winds should be southerly early becoming more westerly later in the day.

    OUTLOOK (THURSDAY-SATURDAY):

High pressure aloft builds on Thursday.  Showers are sill possible early in the day but should end as the air mass stabilizes.  Mixing heights should remain favorable for good smoke dispersal however and transport winds will be generally west-southwest early, becoming northwesterly later in the day.  Expect continued high pressure aloft on Friday and Saturday for dry weather.  Nighttime inversions will trap residual smoke near the ground but daytime heating should push mixing heights 5000 feet for good smoke dispersal conditions.  Transport winds late in the week will be generally northerly, but light.

2.  DISPERSION

WEDNESDAY
Mixing height 2700 - 3700 ft during the morning.  Mixing height rises to above 5000 ft during the afternoon then lowers to 3100 - 4100 ft during the evening.

Transport wind ESE to S at 6 - 10 mph during the morning.  Transport wind shifts to SW to W and increases to 12 - 22 mph during the afternoon and evening.

Surface wind light and variable and controlled by local terrain during the morning.  Surface wind increases to WSW to WNW at 12 - 22 mph during the afternoon and evening.

OUTLOOK:

THURSDAY
Mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon.  Transport wind SW to W at 15 - 25 mph.  Surface wind S to SW at 6 - 10 mph during the morning becoming WSW to WNW at 10 - 20 mph during the afternoon.

FRIDAY
Mixing height 3500 - 4500 ft during the morning rising above 5000 ft during the afternoon.  Transport wind light and variable.  Surface wind light and variable during the morning becoming WNW to NNW at 4 - 8 mph during the afternoon.

SATURDAY
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 during the morning becoming WNW to NNW at 4 - 8 mph during the afternoon.

3.  BURNING INSTRUCTIONS FOR ZONES 624 AND 625 INCLUDING THE WALKER
    RANGE PORTION OF ZONE 624
This instruction is valid for burning conducted on Wed, May 13, 2009.
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Avoid ignitions within 12 miles to the ESE through WNW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 20 miles to the ESE through WNW in or near drainages leading to SSRAs.  Care needed in selecting units as smoke will likely fumigate along the ground in wind prone areas.  Watch for shifting transport winds.

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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


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