SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Tuesday, December 9, 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

 

The atmospheric river stream that has given NW Oregon heavy rain is beginning to move northward in response to a ridge trying to build.  Additional rain across the northern mountains on Wednesday will be mainly .50” to 1.00” and the snow level continues over 8000 feet.  Look for partly to mostly sunny skies in the south but otherwise dry.  The warm air aloft is causing mixing to be poor to fair with mainly SW winds.

 

EXTENDED DISCUSSION

 

The ridge will continue to slowly build Thursday with precipitation tapering off.  Rainfall potential in the far northern mountains is .10” to .25” under mostly cloudy skies.  The south will be sunny except for areas of morning fog.  Mixing potential is generally poor with S-SW winds.

 

Friday will be the driest day of the week and there is only a slight chance of rain in the far northern mountains.  Otherwise, the warm ridge causes skies to range from mostly cloudy in the far north to sunny south, after the morning fog.  Mixing is still poor but winds light and variable.

 

On Saturday the ridge will begin to move east in response to an approaching trough.  Up to .10” of rain is possible for the Coast Range and North Cascades while the snow level is still around 7000 feet.  However, poor mixing continues with light and variable wind.

 

2.  DISPERSION

 

WEDNESDAY

 

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

 

MORNING

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

Transport wind SSW to SW at 18 - 30 mph.

Surface wind SSW to SW at 10 - 16 mph.

 

AFTERNOON

Mixing height 1600 - 2600 ft.

Transport wind similar to morning.

Surface wind similar to morning.

 

EVENING

Mixing height 1500 - 2500 ft.

Transport wind SSW to SW at 14 - 28 mph.

Surface wind SSW to SW at 8 - 14 mph.

 

Zone 605-611 and 639 (North Cascades):

 

MORNING

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

Transport wind SW at 18 - 32 mph.

Surface wind SSW to SW at 10 - 18 mph.

 

AFTERNOON

Mixing height 1900 - 2900 ft.

Transport wind similar to morning.

Surface wind similar to morning.

 

EVENING

Mixing height 1500 - 2500 ft.

Transport wind SSW to SW at 18 - 30 mph.

Surface wind S to SW at 10 - 18 mph.

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height below 1000 ft early rising to 1600 - 2600 ft.

Transport wind S to SW at 8 - 12 mph.

Surface wind S to SW at 4 - 8 mph.

 

AFTERNOON

Mixing height 1200 - 2200 ft.

Transport wind SSW to WSW at 6 - 12 mph.

Surface wind SSW to W at 4 - 8 mph.

 

EVENING

Mixing height 1200 - 2200 ft.

Transport wind SSW to WSW at 6 - 10 mph.

Surface wind SSW to WSW at 4 - 8 mph.

 

Zone 616-623 (South Cascades):

 

MORNING

Mixing height below 1000 ft early rising to 1000 - 1700 ft.

Transport wind SSE to SSW at 8 - 12 mph.

Surface wind SSE to SSW at 5 - 9 mph.

 

AFTERNOON

Mixing height 1300 - 2300 ft.

Transport wind S to SW at 6 - 12 mph.

Surface wind S to SW at 6 - 10 mph.

 

EVENING

Mixing height 1000 - 1600 ft.

Transport wind SSE to SSW at 9 - 15 mph.

Surface wind SSE to SSW at 4 - 8 mph.

 

OUTLOOK:

 

THURSDAY

In the north mixing height below 1000 ft early rising to 1600 to 2600 ft by late morning and through the afternoon.  In the south mixing height below 1000 ft during the morning rising to 1000 to 1700 ft during the afternoon.  Transport wind S to SW at 8 - 14 mph.  Surface wind S to SW at 5 - 9 mph during the morning becoming light and variable during the afternoon.

 

FRIDAY

In the north mixing height below 1000 ft early rising to 1400 to 2400 ft by late morning and through the afternoon.  In the south mixing height below 1000 ft throughout the day.  Transport wind light and variable.  Surface wind light and variable.

 

SATURDAY

Mixing height at or below 1000 ft throughout the day.  Transport wind light and variable.  Surface wind light and variable.

 

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

    - Valid for burning done Wednesday, December 10, 2025.

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Coast Range

 

***Avoid ignitions before 10 a.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, 615, and 616 west of R8W

Units should be 1200 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 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.

 

Zone 618, 619, and 620

Use standard guidance matrix - see section 5 below.  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  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 12 miles apart, and 12 miles from downwind SSRAs.

 

 

Siskiyous

 

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

 

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