SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Tuesday, May 19, 2026       2:30 PM      Sherri Pugh

 

1.  DISCUSSION AND FORECAST FOR THE WESTERN OREGON AREA FORECAST ZONES 601-623 and 639

 

SHORT-TERM DISCUSSION

 

Most of the region will be dry under the influence of upper-level ridging just offshore with N flow aloft for Wednesday.  Isolated showers are possible in far northern zones.  Surface winds will be generally from N while transport winds will come from NW-N.  Temperatures will be near or above seasonable.  Mixing heights will be fair to good.

 

EXTENDED DISCUSSION

 

Flow aloft will be from NW with upper-level ridging on Thursday.  Temperatures will climb well above average.  Winds will be variable and offshore at times with dry weather.  Mixing heights will be fair to poor on the coast and higher inland.

 

The upper-level ridge begins to weaken and flatten on Friday with light NW flow aloft.  Temperatures continue well above seasonable.  Winds will be from N on the coast and W-NW for the Cascades.  Mixing heights will be from fair to good.

 

Saturday will have light SW flow aloft.  Winds will come from WSW-NNW.  Mixing heights will be fair to good.  Dry weather will have well above average temperatures.

 

2.  DISPERSION

 

WEDNESDAY

 

Zone 601, 602, 603 and 612 (North Coast Range):

 

MORNING

Mixing height below 500 ft early rising to 2300 - 3300 ft by late morning.

Transport wind NNW to NNE at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 2700 - 3700 ft.

Transport wind similar to morning.

Surface wind increases to NNW to NNE at 4 - 8 mph.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind NW to N at 6 - 10 mph.

Surface wind NW to N at 4 - 8 mph.

 

Zone 605-611, 639 and 616-623 (North and South Cascades):

 

MORNING

Mixing height below 500 ft early rising to 2700 - 3700 ft by late morning.

Transport wind NW to N at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 3500 - 4500 ft.

Transport wind WNW to NNW at 4 - 8 mph.

Surface wind similar to morning.

 

EVENING

Mixing height 1000 - 1500 ft.

Transport wind NNW to NNE at 4 - 8 mph.

Surface wind similar to afternoon.

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height below 500 ft early rising to 2300 - 3300 ft by late morning.

Transport wind N to NE at 6 - 10 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 2300 - 3300 ft.

Transport wind similar to morning.

Surface wind increases to NNW to NNE at 4 - 8 mph.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

 

OUTLOOK:

 

THURSDAY

In the Coast Range mixing height below 1000 ft early rising to 1600 to 2600 ft by late morning rising to 2200 to 3200 ft during the afternoon.  In the Cascades mixing height below 1000 ft early rising to 2200 to 3200 ft by late morning rising to 4000 to 5000 ft during the afternoon.  Transport wind NNE to ENE at 4 - 8 mph.  Surface wind light and variable.

 

FRIDAY

In the Coast Range mixing height below 1000 ft early rising to 1000 to 2000 ft by late morning rising to 1800 to 2800 ft during the afternoon.  In the Cascades mixing height below 1000 ft early rising to 2100 to 3100 ft by late morning rising to 3600 to 4600 ft during the afternoon.  Transport wind light and variable during the morning becoming WNW to NNW at 4 - 8 mph during the afternoon.  Surface wind light and variable during the morning becoming WNW to NNW at 4 - 8 mph during the afternoon.

 

SATURDAY

Mixing height below 1000 ft early rising to 1600 to 2600 ft by late morning rising to 2900 to 3900 ft during the afternoon.  Transport wind WSW to NW at 4 - 8 mph.  Surface wind W to NW at 4 - 8 mph.

 

3.  BURNING INSTRUCTIONS FOR ALL ZONES IN THE WESTERN OREGON AREA

    - Valid for burning done Wednesday, May 20, 2026.

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

 

Coast Range

 

Zone 601, 612, 615, 616, 618, 619, and 620

Use standard guidance matrix. (See section 5 below.)  Avoid burning directly upwind of coastal SSRAs.

 

Zone 602 and 603

Units should be 600 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Limit tonnage north of Forest Grove/Hillsboro or Sheridan/Willamina in Zone 602.  Higher tonnage is possible south of T17S in Zone 603.  Call the forecaster.

 

 

Cascades

 

Zone 605, 606, 607, 608, 639, 611, 616, 617, and 623

Use standard guidance matrix - see section 5 below.  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  From T12S through T17S in Zone 608 units should be 1200 tons or less, spaced 6 miles apart.  South of T30S in Zone 616 units should be 1000 tons or less, spaced 6 miles apart.  South of T30S in Zone 617 units should be 1000 tons or less, spaced 6 miles apart.

 

Zone 610

Units should be 1200 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs.

 

Zone 620 and 622

Units should be 750 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs.

 

 

Siskiyous

 

Use standard guidance matrix - see section 5 below. Ensure adequate distance from downwind SSRAs for smoke to dissipate.

 

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4.  SPECIAL NOTES:

 

    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

 

    Call the smoke management duty forecaster at (503) 945-7401 to

    discuss burning. Please do not call individual's numbers to

    discuss daily burning. If the forecaster is not available,

    leave a message and they will return your call as soon as possible.

    Avoid calling between 1:30 to 2:45 p.m.

 

    The forecast is available on the Internet at:

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

    Daily/smi.htm

 

    Please ensure your units have been planned and accomplished by

    checking: http://www.oregon.gov/ODF/Fire/Pages/Burn.aspx

 

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

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

    ?id=a7e321dc8fc444b7a33fbc67bc673a3b

 

    The forecast/instruction telephone recording is: (503) 945-7400.

 

    To subscribe to or unsubscribe from the email list for this

    product, please go to the link:

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

 

 

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.

    Example: 300 tons allowed if burned 5 miles from a downwind SSRA.

 

  * 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.