SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Thursday, May 21, 2026       2:30 PM      Gary Votaw

 

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

 

SHORT-TERM DISCUSSION

 

Sunny and warm weather will result on Friday under weak NW flow aloft, temperatures 5-10oF above seasonal averages.  Mixing conditions will be excellent with very light NW winds in the afternoon.

 

EXTENDED DISCUSSION

 

Flow aloft turns W on Saturday and Sunday.  Sunny skies continue the warming trend with temperatures reaching 10-15oF above normal on both days.  Burning potential is still excellent along with W transport winds.

 

An upper trough is expected to arrive at the coast on Monday causing areas of showers in NE Oregon, rainfall typically around .10” and mostly in mountains.  Conditions otherwise will be partly sunny and cooler but temperatures still well above normal.  Mixing conditions are very good with winds trending NW in the afternoon.

 

2.  DISPERSION

 

FRIDAY

 

Zone 640, 642, and 644 West of R35E:

Mixing height below 1000 ft early rising above 5000 ft by late morning and throughout the afternoon.

 

Transport wind light and variable and controlled by local terrain during the morning.  Transport wind increases to WSW to NW at 4 - 8 mph during the afternoon then shifts to NNW to NNE at 6 - 12 mph during the evening.

 

Surface wind light and variable and controlled by local terrain.

 

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

Mixing height below 1000 ft early rising above 5000 ft by late morning and throughout the afternoon.

 

Transport wind light and variable and controlled by local terrain during the morning.  Transport wind increases to WNW to NNW at 4 - 8 mph during the afternoon then shifts to NNE to ENE at 6 - 10 mph during the evening.

 

Surface wind light and variable and controlled by local terrain.

 

OUTLOOK:

 

SATURDAY

Mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon.  Transport wind SSW to WSW at 6 - 10 mph during the morning becoming WSW to WNW at 10 - 16 mph during the afternoon.  Surface wind light and variable during the morning becoming W to NW at 4 - 8 mph during the afternoon.

 

SUNDAY

Mixing height below 1000 ft early rising to 4000 to 5000 ft by late morning rising above 5000 ft during the afternoon.  Transport wind WSW to WNW at 10 - 16 mph.  Surface wind WSW to WNW at 4 - 8 mph.

 

MONDAY

Mixing height below 1000 ft early rising to 4000 to 5000 ft by late morning rising above 5000 ft during the afternoon.  Transport wind SSW to WSW at 10 - 22 mph during the morning becoming WNW to NNW at 12 - 24 mph during the afternoon.  Surface wind SSW to WSW at 6 - 12 mph during the morning becoming WSW to WNW at 10 - 16 mph during the afternoon.

 

3.  BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646

    - Valid for burning done Friday, May 22, 2026.

    ==================================================================

 

Zone 640, 642, and 644 West of R35E:

Follow standard guidance matrix - see section 5 below - for burning units to the SW through NE of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 10 miles in all directions of SSRAs.  Verify transport winds away from SSRAs if burning in any other direction. 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 WNW through ENE of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 10 miles in all directions of SSRAs.  Verify transport winds away from SSRAs if burning in any other direction. No additional restrictions necessary. 

 

    =========================================================

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.