SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Sunday, November 30, 2025       3:15 PM      Pete Parsons

 

************ ODF Forecast Office Reopens Monday Morning *************

The ODF forecast office is currently closed for Thanksgiving weekend and will reopen at 7 a.m. Monday, December 1st. This forecast includes burning instructions for Monday, December 1st, and an outlook to help you with prescribed-burning planning for the coming week. 

Messages left on the ODF forecast line (503-945-7401) will be received and returned after 7 a.m. on Monday, December 1st.

Happy Holidays!

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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 “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

Building high pressure is drying the air mass this afternoon and bringing sunshine to much of the region.  However, the air mass is very stable with persistent pockets of valley fog and low clouds.  Expect inversions to strengthen overnight with local frost.

On Monday, areas of valley fog and frost will yield to increasing clouds, as NW flow aloft directs a weak weather system into the region from SW British Columbia.  Mixing will remain poor with light NW-N winds across the northern zones veering to N-NE across the southern zones.  Light rain is likely north Monday night with snow levels dropping to 4-5000 feet.

EXTENDED DISCUSSION

On Tuesday, areas of light rain north early will turn to scattered showers in the afternoon.  Rainfall totals should be mostly less than .10”.  Southern zones may get some sprinkles or light showers, as a weak cold front drops SE across the region.  Snow levels will be near 4000 feet north and 5000 feet south.  Cooling aloft will improve daytime mixing with mostly NW winds.

High pressure builds back over the state on Wednesday for a return to dry conditions and poor mixing.  Areas of valley fog will give way to increasing clouds from a warm front in the afternoon.  Light winds should be mostly NW-N across the northern zones, veering to N-NE across the southern zones.

Another warm front maintains mostly cloudy skies on Thursday despite a generally dry NW flow aloft.  Surface temperatures will be near average, but freezing levels around 8000 feet will maintain poor mixing with light S-SW transport winds.

The upper-level ridge finally flattens on Friday, allowing a stronger weather system to spread rain across all zones, especially north.  Snow levels drop to 5000 feet north and 7000 feet south.  Rainfall over .25” is likely north and near .10” south.  Cooling aloft and increasing SW-W winds will dramatically improve mixing.

2.  DISPERSION

 

MONDAY

 

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

 

MORNING

Mixing height below 1000 ft.

Transport wind NNE to ENE at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 1100 - 2100 ft.

Transport wind NNW to NE at 4 - 8 mph.

Surface wind similar to morning.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind shifts to W to NW at 4 - 8 mph.

Surface wind similar to afternoon.

 

Zone 605-611 and 639 (North Cascades):

 

MORNING

Mixing height below 1000 ft.

Transport wind light and variable and controlled by local terrain.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 1000 - 1800 ft.

Transport wind increases to NW to NNE at 4 - 8 mph.

Surface wind similar to morning.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind shifts to WSW to WNW at 4 - 8 mph.

Surface wind similar to afternoon.

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height below 1000 ft.

Transport wind NNE to ENE at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 1000 - 2000 ft.

Transport wind N to NE at 5 - 9 mph.

Surface wind increases to N to NE at 4 - 8 mph.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind NNE to ENE at 6 - 10 mph.

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

 

Zone 616-623 (South Cascades):

 

MORNING

Mixing height below 1000 ft.

Transport wind light and variable and controlled by local terrain.

Surface wind light and variable and controlled by local terrain.

 

AFTERNOON

Mixing height 1000 - 2000 ft.

Transport wind increases to NNW to NNE at 4 - 8 mph.

Surface wind similar to morning.

 

EVENING

Mixing height lowers below 1000 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

 

OUTLOOK:

 

TUESDAY

Mixing height below 1000 ft early rising to 2100 to 3100 ft by late morning rising to 3800 to 4800 ft during the afternoon.  Transport wind WNW to NNW at 8 - 12 mph.  Surface wind W to NW at 4 - 8 mph.

 

WEDNESDAY

Mixing height below 1000 ft during the morning rising to 1300 to 2300 ft during the afternoon.  Transport wind E to SE at 4 - 8 mph during the morning becoming NW to N at 4 - 8 mph during the afternoon.  Surface wind light and variable.

 

THURSDAY

Mixing height below 1000 ft during the morning rising to 1000 to 2000 ft during the afternoon.  Transport wind light and variable during the morning becoming SW to W 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 Monday, December 1, 2025.

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Coast Range

 

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

 

Zone 601, 612, 615, 616, 618, 619, and 620

Use standard guidance matrix - see section 5 below.  Avoid burning directly upwind of coastal SSRAs.

 

Zone 602 and 603

Units should be 1200 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  Avoid ignitions north of Forest Grove/Hillsboro or Sheridan/Willamina in Zone 602.  Higher tonnage is possible south of T17S in Zone 603 - call the forecaster.

 

 

Cascades

 

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

 

Zone 605, 606, 610, and 616

Units should be 900 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.  Verify transport winds away from SSRA if burning within 10 miles of the SSRA in Zone 605 and 606.  South of T30S in Zone 616 units should be 600 tons or less, spaced 12 miles apart.

 

Zone 607, 608, 639, 611, 617, and 623

Use standard guidance matrix - see section 5 below.  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  South of T30S in Zone 617 units should be 600 tons or less, spaced 12 miles apart.

 

Zone 620 and 622

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

 

 

Siskiyous

 

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

 

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.