SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Tuesday, May 5, 2026       2:30 PM      Gary Votaw

 

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

 

SHORT-TERM DISCUSSION

 

An overhead upper ridge controls the weather.  Morning clouds on Wednesday will break, becoming sunny and very warm, 10-15oF above seasonal.  Burning potential is poor in the Coast Range but good for the Cascades with light SW-NW winds.

 

EXTENDED DISCUSSION

 

The ridge remains Thursday for mostly sunny and very warm again.  Mixing will generally become good in the afternoon and winds very light, favoring SW-W.

 

A weak trough arrives on Friday but only to slightly cool the region.  Skies will be partly sunny north and sunny south.  Burning opportunities become mostly good in afternoon with light W-NW winds.

 

The ridge once again rebounds by Saturday with sunny and very warm conditions, and continuing Sunday.  Mixing becomes good in the afternoons with NW-N winds.

 

2.  DISPERSION

 

WEDNESDAY

 

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

 

MORNING

Mixing height below 1000 ft early rising to 1200 - 2200 ft.

Transport wind SW to WNW at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 1200 - 2200 ft.

Transport wind WSW to NW at 6 - 12 mph.

Surface wind similar to morning.

 

EVENING

Mixing height 1000 - 1600 ft.

Transport wind WNW to NNW at 10 - 18 mph.

Surface wind increases to W to NW at 6 - 12 mph.

 

Zone 605-611 and 639 (North Cascades):

 

MORNING

Mixing height below 1000 ft early rising to 1800 - 2800 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 3400 - 4400 ft.

Transport wind WSW to WNW at 10 - 16 mph.

Surface wind similar to morning.

 

EVENING

Mixing height 1000 - 1900 ft.

Transport wind decreases to SW to WNW at 5 - 9 mph.

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

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height below 1000 ft early rising to 1400 - 2400 ft.

Transport wind light and variable and controlled by local terrain.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 1700 - 2700 ft.

Transport wind increases to W to NW at 6 - 12 mph.

Surface wind increases to W to NW at 6 - 10 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 616-623 (South Cascades):

 

MORNING

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

Transport wind SW to W at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height rising above 5000 ft.

Transport wind similar to morning.

Surface wind similar to morning.

 

EVENING

Mixing height 2700 - 3700 ft.

Transport wind WNW to NW at 8 - 14 mph.

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

 

OUTLOOK:

 

THURSDAY

In the north mixing height below 1000 ft early rising to 2200 to 3200 ft by late morning rising to 3400 to 4400 ft during the afternoon.  In the south mixing height below 1000 ft early rising to 1000 to 2000 ft by late morning rising to 4000 to 5000 ft during the afternoon.  Transport wind SW to W at 4 - 8 mph.  Surface wind light and variable.

 

FRIDAY

In the north mixing height below 1000 ft early rising to 1100 to 2100 ft by late morning rising to 3600 to 4600 ft during the afternoon.  In the south mixing height below 1000 ft early rising to 1800 to 2800 ft by late morning rising to 3500 to 4500 ft during the afternoon.  Transport wind WSW to WNW at 5 - 9 mph.  Surface wind light and variable during the morning becoming W to NW at 5 - 9 mph during the afternoon.

 

SATURDAY

Mixing height below 1000 ft early rising to 2000 to 3000 ft by late morning rising to 3500 to 4500 ft during the afternoon.  Transport wind light and variable during the morning becoming NNW to NNE at 5 - 9 mph during the afternoon.  Surface wind light and variable during the morning becoming WNW to NNW at 4 - 8 mph during the afternoon.

 

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

    - Valid for burning done Wednesday, May 6, 2026.

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

 

Coast Range

 

Zone 601, 612, and 616 east of R9W

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

 

Zone 602 and 603

No burning allowed.  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 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

 

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 900 tons or less, spaced 8 miles apart.

 

Zone 610 and 611

Units should be 900 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.

 

 

Siskiyous

 

Units should be 1500 tons or less, spaced 3 miles apart, and 5 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.