SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Monday, December 22, 2025       2:30 PM      Gary Votaw

 

*********************************************************************

* 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. *

*********************************************************************

1.  DISCUSSION AND FORECAST FOR SOUTH CENTRAL OREGON ZONES 624 AND 625

 

SHORT-TERM DISCUSSION

 

A large offshore upper trough will cause SW flow aloft on Tuesday.  It will spread rain and snow across the area for .10” to .25” of moisture while snow levels rise to 5-6000 feet.  Temperatures will be above average.  Mixing potential in the afternoon is good with mainly S transport winds.

 

EXTENDED DISCUSSION

 

The trough persists offshore and little change is expected on Wednesday and Thursday, except to be windier.  Light showers will provide generally .10” or less on both days with snow levels at 4500-5500 feet.  Good mixing is expected in the afternoons with mainly S winds.

 

The trough is expected to move across Oregon on Friday in a much-weakened form while bringing cooler air.  Light showers persist and surface temperatures fall to average levels.  Snow levels will be 3-4000 feet.  Afternoon mixing potential is still good with strong SW transport winds.

 

2.  DISPERSION

 

TUESDAY

 

Mixing height 1200 - 2200 ft during the morning.  Afternoon mixing height rises to 4300 - 5000 ft then lowers to 4000 - 5000 ft during the evening.

 

Transport wind SE to SSW at 6 - 12 mph during the morning.  Transport wind increases to SSE to SSW at 15 - 25 mph during the afternoon and evening.

 

Surface wind SE to S at 5 - 9 mph.

 

OUTLOOK:

 

WEDNESDAY

Mixing height below 1000 ft early rising to 3100 - 4100 ft by late morning rising to 4000 - 5000 ft during the afternoon.  Transport wind SSE to SSW at 28 - 48 mph during the morning becoming S to SSW at 21 - 37 mph during the afternoon.  Surface wind SSE to S at 10 - 22 mph.

 

THURSDAY

Mixing height below 1000 ft early rising to 1900 - 2900 ft by late morning rising to 4500 - 5000 ft during the afternoon.  Transport wind SSE to S at 30 - 50 mph during the morning becoming SSE to SSW at 25 - 45 mph during the afternoon.  Surface wind ESE to SSE at 16 - 30 mph during the morning becoming SSE to SSW at 15 - 29 mph during the afternoon.

 

FRIDAY

Mixing height below 1000 ft early rising to 4500 - 5000 ft by late morning and through the afternoon.  Transport wind SW to WSW at 28 - 48 mph during the morning becoming SW to WSW at 20 - 34 mph during the afternoon.  Surface wind SSE to SSW at 14 - 28 mph.

 

3.  BURNING INSTRUCTIONS FOR ZONES 624 AND 625 INCLUDING THE WALKER

    RANGE PORTION OF ZONE 624

    - Valid for burning done Tuesday, December 23, 2025.

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

 

Delay ignitions until 10 a.m. Follow standard guidance matrix - see section 5 below - for burning units to the SE through SSW of SSRAs.  No additional restrictions necessary. 

 

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

4.  SPECIAL NOTE:

 

    The smoke management forecaster is available at (503)

    945-7401.  The smoke management forecaster is available

    to discuss specific burns.  The duty forecaster phone

    number is (503) 945-7401. Please call this number and

    not individual's numbers to discuss daily burning. Please

    avoid calling between 1:30 to 2:45 p.m.

 

    http://www.odf.state.or.us/DIVISIONS/protection/fire_protection/

    Daily/lmt.htm

 

    To subscribe to or unsubscribe from the email list for this

    product, please go to the link:

    http://weather.smkmgt.com/mailman/listinfo/

 

    Please ensure your units have been planned and accomplished by

    checking: http://oregon.gov/ODF/FIRE/SMP/dailysmoke.shtml

 

    A map of planned and/or accomplished burns is located at:

    http://geo.maps.arcgis.com/apps/webappviewer/index.html

    ?id=a7e321dc8fc444b7a33fbc67bc673a3b

 

 

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.

 

  * 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.