SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Tuesday, April 14, 2026       2:30 PM      Gary Votaw

 

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

 

SHORT-TERM DISCUSSION

 

Rain and snow will be widespread on Wednesday.  A cold upper-level trough reaches the coast during the day while a cold front passes through East Oregon.  Precipitation looks to be typically .25” or less but reaching .50” in mountains.  Temperatures will be below seasonal levels as snow levels fall late to 3000 feet.  Burning potential is excellent with SW winds trending W-NW in afternoon and evening.

                                          

EXTENDED DISCUSSION

 

The trough moves into Idaho Thursday and leaves behind N flow aloft.  Expect areas of light snow but clouds decrease in afternoon, temperatures around 15oF below normal.  Cold air aloft helps mixing heights stay excellent in NW winds.

 

On Friday sunny skies are underneath decreasing NNW flow aloft, warmer but temperatures still below normal.  Burning potential is still very good with light W winds.

 

A ridge keeps Saturday mostly sunny while warmer still.  Afternoon mixing will be very good with S-SW winds.

 

2.  DISPERSION

 

WEDNESDAY

 

Zone 640, 642, and 644 West of R35E:

Mixing height above 5000 ft throughout the day.

 

Transport wind WSW to W at 18 - 32 mph.

 

Surface wind WSW to WNW at 6 - 12 mph during the morning and afternoon.  Surface wind increases to W to NW at 10 - 16 mph during the evening.

 

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

Mixing height above 5000 ft throughout the day.

 

Transport wind SSW to SW at 15 - 29 mph during the morning.  Transport wind shifts to WNW to NW at 15 - 29 mph during the afternoon then increases to W to NW at 25 - 45 mph during the evening.

 

Surface wind SSE to SW at 6 - 12 mph during the morning.  Surface wind shifts to NW to NNW and increases to 10 - 16 mph during the afternoon and evening.

 

OUTLOOK:

 

THURSDAY

Mixing height 3800 to 4800 ft during the morning rising above 5000 ft during the afternoon.  Transport wind WNW to NNW at 15 - 25 mph.  Surface wind WNW to NNW at 6 - 10 mph.

 

FRIDAY

Mixing height below 1000 ft early rising to 3500 to 4500 ft by late morning rising above 5000 ft during the afternoon.  Transport wind WSW to WNW at 6 - 10 mph.  Surface wind light and variable.

 

SATURDAY

Mixing height below 1000 ft early rising to 3500 to 4500 ft by late morning rising above 5000 ft during the afternoon.  Transport wind S to SW at 9 - 15 mph.  Surface wind SE to SSW at 4 - 8 mph.

 

3.  BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646

    - Valid for burning done Wednesday, April 15, 2026.

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Zone 640, 642, and 644 West of R35E:

Follow standard guidance matrix - see section 5 below - for burning units to the WSW through WNW of SSRAs.  No additional restrictions necessary. 

 

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

Follow standard guidance matrix - see section 5 below - for burning units to the SSW through NW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 5 miles to the SSW through NNW in or near drainages leading to SSRAs.  Watch for shifting transport winds. 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.