SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Wednesday, November 26, 2025       2:30 PM      Gary Votaw

 

****************** Thanksgiving Weekend Schedule ********************

The ODF forecast office will be closed from Thursday, November 27th through Sunday, November 30th.  This forecast includes burning instructions through Sunday (4 days).  Burning instructions for Monday, December 1st, will be issued Sunday afternoon. 

For questions regarding prescribed burning planned for this period, please call the forecast office at 503-945-7401 prior to 5 p.m. on Wednesday, November 26th or after 7 a.m. on Monday, December 1st.

Happy Thanksgiving!

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1.  DISCUSSION AND FORECAST FOR NORTHEAST FORECAST AREA ZONES 637-646

 

SHORT-TERM DISCUSSION

 

An upper-level ridge will still dominate Thursday while a trough approaches from the west.  The trough will be too late to improve burning conditions though winds turn SW and increase.  There may be some very light rain in the north portion and snow above 6-7000 feet, and temperatures reach 5-10oF above average.  Look for poor to fair mixing in afternoon with increasing SW transport winds.

 

EXTENDED DISCUSSION

 

The upper trough arrives Thursday night then moves east late Friday, causing much improved mixing conditions.  Rain potentially provides .10” to .25” of moisture before tapering off during the day while snow levels will be near 5000 feet.  Very good mixing is expected by afternoon with NW-NNW winds.

 

Flow aloft will be NW on Saturday, to cause partly sunny skies and near seasonal temperatures.  Mixing will generally be good by the afternoon with SW transport winds.

 

An upper trough is expected to develop in the NW flow for a chance of very light rain or snow, mainly Saturday night.  The trough moves SE early Sunday, leaving behind reinforced NW-N flow aloft and clearing skies.  Mixing will be poor with light and variable winds.

 

2.  DISPERSION

 

THURSDAY

 

Zone 640, 642, and 644 West of R35E:

Mixing height below 1000 ft during the morning.  Afternoon mixing height rising to 2200 - 3200 ft then lowering to 1000 to 2000 ft during the evening.

 

Transport wind SSE to SSW at 9 - 15 mph during the morning.  Transport wind increases to SSW to SW at 16 - 30 mph during the afternoon then decreases to SW to W at 13 - 25 mph during the evening.

 

Surface wind light and variable and controlled by local terrain during the morning.  Surface wind increases to SSE to SW at 6 - 12 mph during the afternoon then shifts to SSW to W at 5 - 9 mph during the evening.

 

Zone 637, 643, 645, 646, and 644 East of R34E:

Mixing height below 1000 ft during the morning.  Afternoon mixing height rising to 1300 - 2300 ft then lowering to 1000 to 2000 ft during the evening.

 

Transport wind E to ESE at 8 - 12 mph during the morning.  Transport wind shifts to SSW to SW at 10 - 16 mph during the afternoon then increases to SSW to WSW at 15 - 29 mph during the evening.

 

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

 

OUTLOOK:

 

FRIDAY

Mixing height 3000 to 4000 ft during the morning rising above 5000 ft during the afternoon.  Transport wind WSW to WNW at 16 - 30 mph during the morning becoming NW to NNW at 13 - 25 mph during the afternoon.  Surface wind WSW to WNW at 8 - 14 mph during the morning becoming WNW to NNW at 6 - 12 mph during the afternoon.

 

SATURDAY

Mixing height below 1000 ft early rising to 1000 to 2000 ft by late morning rising above 5000 ft during the afternoon.  Transport wind SSE to SSW at 6 - 10 mph during the morning becoming SSW to WSW at 8 - 14 mph during the afternoon.  Surface wind SE to S at 4 - 8 mph during the morning becoming light and variable during the afternoon.

 

SUNDAY

Mixing height below 1000 ft early rising to 1000 to 2000 ft by late morning and through the afternoon.  Transport wind light and variable.  Surface wind light and variable.

 

3.  BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646

    - Valid for burning done Thursday through Sunday, November 27 through 30, 2025.

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For Thursday:

 

Zone 640, 642, and 644 West of R35E:

Delay ignitions until 10 a.m.   Follow standard guidance matrix - see section 5 below - for burning units to the SSE through W of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 15 miles to the SSE through WNW in or near drainages leading to SSRAs.  No additional restrictions necessary. 

 

Zone 637, 643, 645, 646, and 644 East of R34E:

Delay ignitions until 10 a.m.   Follow standard guidance matrix - see section 5 below - for burning units to the E through WSW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 15 miles in all directions of SSRAs.  Watch for shifting transport winds. No additional restrictions necessary. 

 

For Friday:

 

Follow standard guidance matrix - see section 5 below - for burning units to the WNW through N of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 10 miles in all directions of SSRAs.  No additional restrictions necessary. 

 

For Saturday:

 

Delay ignitions until 10 a.m.   Follow standard guidance matrix - see section 5 below - for burning units to the SE through NW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 10 miles in all directions of SSRAs.  Watch for shifting transport winds. No additional restrictions necessary. 

 

For Sunday:

 

Delay ignitions until 10 a.m.   Follow standard guidance matrix - see section 5 below - for burning units in all directions of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 30 miles in all directions of SSRAs.  No additional restrictions necessary. 

 

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4.  SPECIAL NOTE:

 

    The ODF forecast smoke zones differ from the NWS fire zones and

    are available at:

    https://www.oregon.gov/odf/fire/documents/smoke-forecast-zone-map.pdf

 

    The smoke management forecaster is available at (503)-

    945-7401. Please call this number and not individual's

    numbers to discuss daily burning.  For large burns (over

    2000 tons) or burns extending over a considerable period,

    please request a special forecast.  Avoid calling

    between 1:30 to 2:45 p.m.

 

    http://www.odf.state.or.us/DIVISIONS/protection/fire_protection/

    Daily/neo.htm

 

    To subscribe to or unsubscribe from the email list for this

    product, please go to the link:

    http://weather.smkmgt.com/mailman/listinfo/

 

    Please ensure your units have been planned and accomplished by

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

 

    A map of planned and/or accomplished burns is located at:

    http://geo.maps.arcgis.com/apps/webappviewer/index.html

    ?id=a7e321dc8fc444b7a33fbc67bc673a3b

 

 

5.  STANDARD GUIDANCE MATRIX:

 

  * Greater than 5000 ft mixing height: Limit to 150 tons per mile

    from downwind SSRAs.

    Example: 75 tons allowed if burned a half mile from a downwind

    SSRA.

 

  * 3000 - 5000 ft mixing height: Limit to 50 tons per mile if

    burning within 5 miles of downwind SSRAs. Limit to 100 tons

    per mile if burning 5 miles or beyond downwind SSRAs.

    Example #1: 200 tons allowed if burned 4 miles from a downwind

    SSRA.

    Example #2: 500 tons allowed if burned 5 miles from a downwind

    SSRA.

 

  * Less than 3000 ft mixing height: No burning within 5 miles of

    downwind SSRAs. Limit to 60 tons per mile from downwind SSRAs.

 

  * Ensure adequate spacing between units when burning near downwind

    SSRAs.

 

  * Use of polyethylene (PE) sheeting on greater than 75 percent of

    piles in a unit with 60 percent coverage per pile will allow a

    50 percent increase in tonnage over the existing instruction tonnage

    for that zone.

 

  * All exceptions must be coordinated with the duty forecaster

    prior to ignition.

 

 

6.  BURN MONITORING:

 

    Burns over 2000 tons must be monitored (OAR 629-048-0230(3) -

    7/1/14). Monitoring of all burns is highly recommended for both

    smoke management purposes and wildfire potential.