SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Friday, December 12, 2025       2:30 PM      Gary Votaw

 

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* Special Protection Zone (SPZ) provisions apply from November 15 through February 15.  Prescribed burning is not allowed in an SPZ from December 1 through February 15 on days when the daily woodstove “Ordinance” is either “Red,” “Exempt Wood Burning Device,” or “No Burning Period.”  Burning is allowed inside of SPZs all other days, but please use extra precautions and limit forestland burning to units that will not worsen air quality within nearby SSRAs. *

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

 

SHORT-TERM DISCUSSION

 

An overhead and very warm upper-level ridge begins to move eastward on Saturday as SW flow increases.  Areas of morning fog turn to partly to mostly sunny skies in afternoon as very warm conditions persist.  Temperatures in mountains will be 10oF to 20oF above average.  Even warmer air remains aloft to keep mixing very poor and winds light and variable but favoring SE-SW.

 

An upper trough in the Gulf of Alaska will begin to impact the area on Sunday.  Light rain will reach NW Oregon late while clouds increase elsewhere.  Mixing potential remains poor with very light S-SW transport winds.

 

EXTENDED DISCUSSION

 

The trough remains centered well offshore on Monday, but the SW flow aloft increases over West Oregon along with rain.  Precipitation of .50” to 1.00” during the day will be typical on the coast and in northern mountains with snow above 8000 feet.  Mixing will improve with increasing S-SW winds.

 

The strongest part of the trough approaches on Tuesday with a cold front arriving in the evening.  Additional rain of 1.00” to 1.50” will be common during the day for the mountains with a snow level falling to 6000 feet north late in afternoon but 8000 feet south.  Mixing potential is very good with mainly SW winds.

 

Lighter precipitation will continue Wednesday with snow levels falling closer to near mountain pass levels.  Mixing potential is very good with S-SW winds.

 

2.  DISPERSION

 

SATURDAY

 

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

 

MORNING

Mixing height below 1000 ft.

Transport wind ESE to SSE at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height remains below 1000 ft.

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

Surface wind similar to morning.

 

EVENING

Mixing height remains 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.

Transport wind SE to S at 5 - 9 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height remains below 1000 ft.

Transport wind SSE to SW at 5 - 9 mph.

Surface wind similar to morning.

 

EVENING

Mixing height remains below 1000 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height below 1000 ft.

Transport wind S to SW at 5 - 9 mph.

Surface wind SSW to WSW at 4 - 8 mph.

 

AFTERNOON

Mixing height 1000 - 1600 ft.

Transport wind similar to morning.

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

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind similar to afternoon.

Surface wind increases to SSE to SSW at 6 - 10 mph.

 

Zone 616-623 (South Cascades):

 

MORNING

Mixing height below 1000 ft.

Transport wind ESE to SSE at 5 - 9 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 1000 - 1500 ft.

Transport wind SSE to SSW at 5 - 9 mph.

Surface wind similar to morning.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind ESE to S at 6 - 10 mph.

Surface wind similar to afternoon.

 

OUTLOOK:

 

SUNDAY

Mixing height below 1000 ft during the morning rising to 1000 to 1700 ft during the afternoon.  Transport wind S to SW at 6 - 10 mph.  Surface wind light and variable.

 

MONDAY

Mixing height below 1000 ft during the morning rising to 2600 to 3600 ft during the afternoon.  Transport wind S to SW at 6 - 10 mph during the morning becoming SSW to SW at 24 - 42 mph during the afternoon.  Surface wind light and variable during the morning becoming S to SW at 10 - 16 mph during the afternoon.

 

TUESDAY

In the north mixing height 2800 to 3800 ft during the morning rising above 5000 ft during the afternoon.  In the south mixing height 1600 to 2600 ft during the morning rising to 4200 to 5000 ft during the afternoon.  Transport wind SSW to SW at 13 - 25 mph during the morning becoming SW to WSW at 20 - 34 mph during the afternoon.  Surface wind S to SW at 8 - 12 mph.

 

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

    - Valid for burning done Saturday through Monday, December 13 through 15, 2025.

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For Saturday:

 

Coast Range

 

***Avoid ignitions before 10 a.m. in all zones.  Complete ignitions by 2:30 p.m. in all zones.***

 

Zone 601, 612, and 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 in Zone 616 - call the forecaster.

 

Zone 602 and 603

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

 

Zone 615, 616 west of R8W, 618, 619, and 620

Use standard guidance matrix - see section 5 below.  Avoid burning directly upwind of the North Bend/Coos Bay SSRA.

 

 

Cascades

 

***Avoid ignitions before 10 a.m. in all zones.  Complete ignitions by 2:30 p.m. in all zones.***

 

Zone 605, 606, and 616

Units should be 600 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  In zone 616 avoid ignitions north of T24S.  South of T29S higher tonnage is possible - call the forecaster.

 

Zone 607, 608, 639, 610, 617, and 623

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

 

Zone 611

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

 

Zone 620 and 622

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

 

 

Siskiyous

 

***Avoid ignitions before 10 a.m.  Complete ignitions by 2:30 p.m.***

 

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

 

For Sunday:

 

Coast Range

 

***Avoid ignitions before 10 a.m. in all zones.  Complete ignitions by 2:30 p.m. in all zones.***

 

Zone 601

Units should be 1500 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  North of Tillamook, use standard guidance matrix - see section 5 below.

 

Zone 602 and 603

Units should be 300 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  North of T3N in Zone 602, use standard guidance matrix - see section 5 below.  Units may be 900 tons or less, spaced 12 miles apart, south of the Siuslaw River in Zone 603.

 

Zone 612

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

 

Zone 615, 616 west of R8W, 618, 619, and 620

Use standard guidance matrix - see section 5 below.  Avoid burning directly upwind of the North Bend/Coos Bay SSRA.

 

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

 

***Avoid ignitions before 10 a.m. in all zones.  Complete ignitions by 2:30 p.m. in all zones.***

 

Zone 605, 606, 607, 608, 639, 610, 617, 620, 622, and 623

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

 

Zone 611

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

 

Zone 616

Units should be 600 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  Avoid ignitions north of T24S.  South of T29S higher tonnage is possible - call the forecaster.

 

 

Siskiyous

 

***Avoid ignitions before 10 a.m.  Complete ignitions by 2:30 p.m.***

 

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

 

For Monday:

 

Coast Range

 

***Avoid ignitions before 10 a.m. in all zones.***

 

Zone 601

Units should be 1000 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  North of Tillamook, use standard guidance matrix - see section 5 below.

 

Zone 602 and 603

Units should be 300 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  North of T3N in Zone 602, use standard guidance matrix - see section 5 below.  Units may be 900 tons or less, spaced 12 miles apart, south of the Siuslaw River in Zone 603.

 

Zone 612 and 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 in Zone 616 - call the forecaster.

 

Zone 615, 616 west of R8W, 618, 619, and 620

Use standard guidance matrix - see section 5 below.  Avoid burning directly upwind of the North Bend/Coos Bay SSRA.  South of T35S in Zone 620 units should be 750 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.

 

 

Cascades

 

***Avoid ignitions before 10 a.m. in all zones.***

 

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

 

 

Siskiyous

 

***Avoid ignitions before 10 a.m.***

 

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.