SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Thursday, May 7, 2026       2:30 PM      Gary Votaw

 

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

 

SHORT-TERM DISCUSSION

 

A quickly weakening trough arrives on Friday, brushing across the north portion of the area, cooling temperatures but still a little above average.  Areas of morning clouds will break and become generally sunny in the afternoon.  Burning opportunities for the afternoon are generally fair in the Coast Range but good for the Cascades with WSW-NW winds.

 

EXTENDED DISCUSSION

 

The ridge rebounds on Saturday with weak SW flow aloft to cause the warmest day of the week.  Mostly sunny skies push temperatures to reach 10-20oF above seasonal levels.  Mixing conditions will be mostly good in the afternoon with very light winds, favoring SW-WNW.  

 

Another weak trough brushes across the area on Sunday, mainly north of Oregon.  It brings cooler temperatures closer to normal under partly to mostly sunny skies.  Mixing becomes moderate to good with very light NW winds. 

 

The ridge once again builds on Monday with sunny skies and returning temperatures 10-20oF above normal.  Mixing potential is good in the afternoon with very light winds, favoring NNW-NE.

 

2.  DISPERSION

 

FRIDAY

 

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

 

MORNING

Mixing height below 1000 ft early rising to 1900 - 2900 ft.

Transport wind SW to W at 6 - 10 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 2500 - 3500 ft.

Transport wind WSW to WNW at 6 - 12 mph.

Surface wind similar to morning.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind WNW to NNW at 6 - 10 mph.

Surface wind similar to afternoon.

 

Zone 605-611 and 639 (North Cascades):

 

MORNING

Mixing height below 1000 ft early rising to 1900 - 2900 ft.

Transport wind SW to W at 10 - 16 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height rising to 3700 - 4700 ft.

Transport wind WSW to WNW at 10 - 22 mph.

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

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind decreases to WSW to WNW at 6 - 10 mph.

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 1600 - 2600 ft.

Transport wind light and variable and controlled by local terrain.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 2300 - 3300 ft.

Transport wind increases to WSW to NW at 6 - 10 mph.

Surface wind increases to W to NW at 6 - 10 mph.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind WNW to NNW at 4 - 8 mph.

Surface wind similar to afternoon.

 

Zone 616-623 (South Cascades):

 

MORNING

Mixing height below 1000 ft early rising to 2300 - 3300 ft.

Transport wind SW to W at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height rising to 4300 - 5000 ft.

Transport wind WSW to NW at 6 - 10 mph.

Surface wind similar to morning.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind shifts to NW to N at 6 - 10 mph.

Surface wind similar to afternoon.

 

OUTLOOK:

 

SATURDAY

Mixing height below 1000 ft early rising to 2600 to 3600 ft by late morning rising to 4200 to 5000 ft during the afternoon.  Transport wind ENE to ESE at 4 - 8 mph during the morning becoming SW to WNW at 4 - 8 mph during the afternoon.  Surface wind light and variable.

 

SUNDAY

Mixing height below 1000 ft early rising to 1700 to 2700 ft by late morning rising to 3000 to 4000 ft during the afternoon.  Transport wind WNW to NNW at 5 - 9 mph.  Surface wind light and variable during the morning becoming WNW to NNW at 6 - 10 mph during the afternoon.

 

MONDAY

In the north mixing height below 1000 ft early rising to 2600 to 3600 ft by late morning rising to 3700 to 4700 ft during the afternoon.  In the south mixing height below 1000 ft early rising to 1200 to 2200 ft by late morning rising to 3500 to 4500 ft during the afternoon.  Transport wind light and variable during the morning becoming NNW to NE at 5 - 9 mph during the afternoon.  Surface wind light and variable.

 

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

    - Valid for burning done Friday, May 8, 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 and 603

Units should be 400 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Limit burning in or near corridors.  Higher tonnage is possible south of the Siuslaw River in Zone 603.  Call the forecaster.

 

Zone 615 and 616 west of R8W

Units should be 900 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.

 

Zone 616 east of R9W

Units should be 600 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.

 

Zone 618 and 619

Units should be 1200 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.

 

Zone 620

Units should be 300 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.

 

 

Cascades

 

Zone 605, 606, 607, 608, 639, 616, 617, 622, and 623

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 and 620

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

 

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.