SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Wednesday, May 6, 2026       2:30 PM      Gary Votaw

 

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

 

SHORT-TERM DISCUSSION

 

On Thursday an upper ridge remains overhead.  Clouds in the morning will break to become sunny and very warm in the afternoon, mostly 10oF above seasonal.  Mixing becomes moderate or good in the afternoon as winds are light from WSW-NW.

 

EXTENDED DISCUSSION

 

A quickly weakening trough arrives on Friday and slightly cools the region.  Skies will be partly sunny north and sunny south.  Burning opportunities become good in afternoon with light SW-NW winds.

 

The ridge again rebounds for Saturday and Sunday with weak SW flow aloft.  Sunny and very warm conditions are expected both days, mainly around 10oF above normal.  Mixing potential is good in the afternoons with NW winds.

 

2.  DISPERSION

 

THURSDAY

 

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

 

MORNING

Mixing height below 1000 ft early rising to 2100 - 3100 ft.

Transport wind light and variable and controlled by local terrain.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 3100 - 4100 ft.

Transport wind similar to morning.

Surface wind similar to morning.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

 

Zone 605-611 and 639 (North Cascades):

 

MORNING

Mixing height below 1000 ft early rising to 2400 - 3400 ft.

Transport wind SW to WNW at 6 - 10 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height rising to 3500 - 4500 ft.

Transport wind WSW to WNW at 9 - 15 mph.

Surface wind increases to SW to WNW at 4 - 8 mph.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind becomes light and variable and controlled by local terrain.

Surface wind becomes light and variable and controlled by local terrain.

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height below 1000 ft early rising to 1500 - 2500 ft.

Transport wind light and variable and controlled by local terrain.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height rising to 3000 - 4000 ft.

Transport wind increases to WSW to NW at 5 - 9 mph.

Surface wind increases to W to NW at 4 - 8 mph.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

 

Zone 616-623 (South Cascades):

 

MORNING

Mixing height below 1000 ft early rising to 2800 - 3800 ft.

Transport wind SW to WNW at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height rising to 4300 - 5000 ft.

Transport wind increases to WSW to WNW at 9 - 15 mph.

Surface wind increases to WSW to WNW at 5 - 9 mph.

 

EVENING

Mixing height 2000 - 3000 ft.

Transport wind W to NW at 6 - 12 mph.

Surface wind W to NW at 5 - 9 mph.

 

OUTLOOK:

 

FRIDAY

Mixing height below 1000 ft early rising to 2700 to 3700 ft by late morning rising to 3800 to 4800 ft during the afternoon.  Transport wind SW to W at 6 - 12 mph.  Surface wind light and variable during the morning becoming WSW to NW at 4 - 8 mph during the afternoon.

 

SATURDAY

In the north mixing height below 1000 ft early rising to 2400 to 3400 ft by late morning rising to 3800 to 4800 ft during the afternoon.  In the south mixing height below 1000 ft early rising to 1400 to 2400 ft by late morning rising to 3500 to 4500 ft during the afternoon.  Transport wind light and variable during the morning becoming NW to N at 5 - 9 mph during the afternoon.  Surface wind light and variable.

 

SUNDAY

Mixing height below 1000 ft early rising to 1800 to 2800 ft by late morning rising to 3300 to 4300 ft during the afternoon.  Transport wind WNW to NNW at 4 - 8 mph during the morning becoming WNW to NNW at 8 - 14 mph during the afternoon.  Surface wind light and variable during the morning becoming W to NW at 6 - 10 mph during the afternoon.

 

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

    - Valid for burning done Thursday, May 7, 2026.

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

 

Coast Range

 

Zone 601 and 612

Units should be 1000 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Restrict units in or near corridors to 500 tons or less.

 

Zone 602, 603, and 620

Units should be 300 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Limit burning in or near corridors.

 

Zone 615 and 616 west of R8W

Units should be 1200 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.

 

Zone 616 east of R9W

Units should be 750 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.

 

Zone 618 and 619

Use standard guidance matrix. (See section 5 below.)

 

 

Cascades

 

All zones except Zone 610 and 611

Use standard guidance matrix - see section 5 below.  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  From T15S through T20S in Zone 608 units should be 1200 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 611

Units should be 1500 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs.

 

 

Siskiyous

 

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

 

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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.