SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Saturday, May 23, 2015       2:40 PM      Tom Jenkins

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Please note that ODF Smoke Management will be closed on Monday to observe the Memorial Day holiday. Smoke Management Forecasts and Instructions will be issued on Sunday afternoon to cover both Monday and Tuesday.

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

 

SHORT-TERM DISCUSSION

An upper-level trough exits southern Oregon before sunrise, allowing the atmosphere to stabilize. Onshore flow will build slowly throughout Sunday, creating excellent mixing conditions. The atmosphere will continue to stabilize after sunset, forming a weak inversion.

EXTENDED DISCUSSION

A weak upper-level trough will skim the California border before sunrise, breaking the inversion and improving mixing early on Memorial Day. Onshore flow will strengthen, and afternoon showers will pop up over the Cascades. An upper-level trough will enter central Oregon after sunset, keeping mixing conditions fair overnight. The remains of a Cold Front will produce morning showers Tuesday. This will help enhance mixing conditions and produce isolated thunderstorms Tuesday afternoon in the unstable atmosphere. An upper-level ridge will begin to build overnight Tuesday, stabilizing the atmosphere. Onshore flow will weaken, and warming air aloft will restrict mixing on Wednesday. A surface ridge will form west of the Cascades, stabilizing the atmosphere even more as an inversion forms after sunset.

2.  DISPERSION

 

SUNDAY

 

Mixing height above 5000 ft throughout the day.  Mixing height lowers to 3500 - 4500 ft during the evening.

 

Transport wind NE to E at 8 - 12 mph during the morning.  Transport wind shifts to NNW to NNE and decreases to 4 - 8 mph during the afternoon and evening.

 

Surface wind light and variable and controlled by local terrain during the morning.  Surface wind increases to NW to N at 5 - 9 mph during the afternoon and evening.

 

OUTLOOK:

 

MONDAY

Mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon.  Transport wind SW to WNW at 4 - 8 mph during the morning becoming WSW to WNW at 8 - 14 mph during the afternoon.  Surface wind SSW to WSW at 4 - 8 mph.

 

TUESDAY

Mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon.  Transport wind W to NW at 5 - 9 mph.  Surface wind WSW to NW at 4 - 8 mph during the morning becoming NW to NNW at 8 - 12 mph during the afternoon.

 

WEDNESDAY

Mixing height below 1000 ft early rising to 2500 - 3500 ft by late morning rising above 5000 ft during the afternoon.  Transport wind ESE to SSE at 37 - 57 mph during the morning becoming light and variable during the afternoon.  Surface wind light and variable during the morning becoming WSW to NW at 5 - 9 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 Sunday, May 24, 2015.

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Avoid ignitions within 10 miles to the NNW through E of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 15 miles in all directions of SSRAs.  Verify transport winds away from SSRAs if burning in any other direction.  Watch for shifting transport winds.  No additional restrictions necessary. 

 

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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_Information

 

    Please ensure your units have been planned and accomplished by checking:

      http://oregon.gov/ODF/FIRE/SMP/dailysmoke.shtml