SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Friday, October 24, 2025       2:30 PM      Gary Votaw

 

************************* Scheduling Note ***************************

Daily written forecasts/instructions have resumed!  The ODF forecast office will be staffed Monday through Friday from 7 a.m. – 5 p.m.  Forecasts will be issued on those afternoons and will include instructions for the following day.  The office will be closed on weekends and on holidays.  Friday’s forecasts will include instructions for Saturday through Monday (through Tuesday, if Monday is a holiday).

As always, please call the forecast office at 503-945-7401, if you need additional help or have questions about smoke clearance.

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******************** Instruction Zones Update ***********************

The National Weather Service recently changed borders and numbering of their fire zones.  ODF will use the previous zone boundaries for smoke management and not change with these updates.

A link to ODF’s smoke forecast zones is at the bottom of the instructions in the Special Notes section. (https://www.oregon.gov/odf/fire/documents/smoke-forecast-zone-map.pdf)

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

 

SHORT-TERM DISCUSSION

 

The strongest part of the upper-level trough will arrive across West Oregon early on Saturday, causing continuing showers and possible thunderstorms.  It will also cause windy conditions and otherwise excellent mixing.  The snow level will lower to around 4500 feet in afternoon as temperatures hover 5-10oF below seasonal.  Additional moisture in mountains during the day will typically be .50” to as much as 1.00”.  Winds will be strong and mostly SW.

 

EXTENDED DISCUSSION

 

Still another trough arrives on Sunday to cause showers to persist but not as windy.  Additional moisture for Saturday night and Sunday may be another .50” to 1.00”.  The snow level in the afternoon ranges from 4000 feet north to 5500 feet south.  Mixing heights will be excellent throughout the day with SW-W transport winds.

 

A weak ridge develops over the area by Monday but with moist flow continuing.  Showers will be lighter and fewer in number with a snow level rising to 5-7000 feet.  Only fair mixing is expected, and winds turn lightly SE-S.

 

The ridge remains on Tuesday, but a trough passes mainly north of the state causing showers to linger across the north half of the region.  Temperatures finally climb back to near seasonal levels.  Mixing becomes moderate to good in the afternoon with SW transport winds trending more W during afternoon.

 

2.  DISPERSION

 

SATURDAY

 

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

 

MORNING

Mixing height above 5000 ft.

Transport wind SW at 26 - 46 mph.

Surface wind SSW to SW at 12 - 20 mph.

 

AFTERNOON

Mixing height above 5000 ft.

Transport wind SW at 24 - 42 mph.

Surface wind SW to WSW at 12 - 24 mph.

 

EVENING

Mixing height remains above 5000 ft.

Transport wind WSW at 25 - 45 mph.

Surface wind SW to W at 10 - 18 mph.

 

Zone 605-611 and 639 (North Cascades):

 

MORNING

Mixing height above 5000 ft.

Transport wind SW at 24 - 42 mph.

Surface wind S to SW at 12 - 20 mph.

 

AFTERNOON

Mixing height above 5000 ft.

Transport wind SW at 27 - 47 mph.

Surface wind SSW to SW at 14 - 24 mph.

 

EVENING

Mixing height remains above 5000 ft.

Transport wind WSW at 24 - 42 mph.

Surface wind decreases to SSW to WSW at 12 - 20 mph.

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height above 5000 ft.

Transport wind SW at 25 - 45 mph.

Surface wind SSW to SW at 12 - 22 mph.

 

AFTERNOON

Mixing height above 5000 ft.

Transport wind similar to morning.

Surface wind SW to WSW at 14 - 24 mph.

 

EVENING

Mixing height remains above 5000 ft.

Transport wind decreases to SW to W at 12 - 24 mph.

Surface wind SW to WSW at 10 - 16 mph.

 

Zone 616-623 (South Cascades):

 

MORNING

Mixing height above 5000 ft.

Transport wind SW at 20 - 36 mph.

Surface wind SSW to WSW at 10 - 18 mph.

 

AFTERNOON

Mixing height above 5000 ft.

Transport wind SW at 22 - 40 mph.

Surface wind increases to SW to WSW at 14 - 24 mph.

 

EVENING

Mixing height remains above 5000 ft.

Transport wind decreases to SW to WSW at 16 - 30 mph.

Surface wind decreases to SSW to WSW at 8 - 15 mph.

 

OUTLOOK:

 

SUNDAY

In the Coast Range mixing height above 5000 ft throughout the day.  In the Cascades mixing height 2200 to 3200 ft during the morning rising above 5000 ft during the afternoon.  Transport wind SSW to SW at 10 - 20 mph during the morning becoming SW to W at 10 - 18 mph during the afternoon.  Surface wind S to SW at 6 - 10 mph during the morning becoming SSW to W at 5 - 9 mph during the afternoon.

 

MONDAY

Mixing height below 1000 ft early rising to 1800 to 2800 ft by late morning and through the afternoon.  Transport wind SE to S at 8 - 12 mph.  Surface wind ESE to SSE at 4 - 8 mph.

 

TUESDAY

In the north mixing height below 1000 ft early rising to 2800 to 3800 ft by late morning rising to 3500 to 4500 ft during the afternoon.  In the south mixing height below 1000 ft early rising to 1500 to 2500 ft by late morning rising to 3000 to 4000 ft during the afternoon.  Transport wind SSW to WSW at 6 - 10 mph during the morning becoming WSW to WNW at 8 - 12 mph during the afternoon.  Surface wind SE to S at 4 - 8 mph during the morning becoming SW to WNW at 5 - 9 mph during the afternoon.

 

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

    - Valid for burning done Saturday through Monday, October 25 through 27, 2025.

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For Saturday:

 

Coast Range

 

All Zones

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

 

 

Cascades

 

All zones except zone 611

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

 

Zone 611

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

 

 

Siskiyous

 

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

 

For Sunday:

 

Coast Range

 

All Zones

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

 

 

Cascades

 

All zones except zone 611

Use standard guidance matrix - see section 5 below.  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  Avoid ignitions north of T24S in Zone 616.

 

Zone 611

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

 

 

Siskiyous

 

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

 

For Monday:

 

Coast Range

 

Zone 601, 602, 603, 612, 615, 616 west of R8W, 618, 619, and 620

Use standard guidance matrix - see section 5 below.  Avoid burning directly upwind of coastal SSRAs.  Higher tonnage is possible south of T29S in Zone 616 - call the forecaster.

 

Zone 616 east of R9W

Units should be 900 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  Higher tonnage is possible south of T29S - call the forecaster.

 

 

Cascades

 

Zone 605 and 606

Units should be 400 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.

 

Zone 607, 608, and 616

Units should be 1000 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.

 

Zone 639, 610, 620, and 623

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

 

Zone 611, 617, and 622

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

 

 

Siskiyous

 

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