SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Thursday, May 14, 2026       2:30 PM      Pete Parsons

 

1.  DISCUSSION AND FORECAST FOR NORTHEAST FORECAST AREA ZONES 637-646

 

SHORT-TERM DISCUSSION

A weak upper-level trough brings some clouds tonight, mainly north, with a risk of a shower over the mountains.  NW winds will slowly relax.  In its wake, a dry and stable westerly flow aloft should bring clearing with excellent daytime mixing on Friday.  Temperatures will be slightly below average with W-NW winds.

EXTENDED DISCUSSION

A stronger upper-level trough pushes the jet stream southward, over Oregon, on Saturday. NW winds and showers increase, especially over higher terrain.  Rainfall totals may locally exceed .10”.  Temperatures should cool to 10-15°F below average with excellent daytime mixing.

Sunday, the upper-level trough slides eastward, to over Idaho, with a cool NW flow aloft over Oregon.  Expect partly cloudy skies with a minimal threat of morning showers.  Temperatures remain about 10-15°F below average with excellent mixing and brisk NW winds.

A NW jet stream stays over the region Monday, as an upper-level ridge slowly builds.  A weak warm front should maintain some clouds, but the threat of rainfall will be minimal and mainly over the NE mountains.  Daytime mixing remains good.  Temperatures will recover to within 5°F of average with continued NW winds.

2.  DISPERSION

 

FRIDAY

 

Zone 640, 642, and 644 West of R35E:

Mixing height below 3000 ft early rising to 3500 - 4500 ft by late morning.  Afternoon mixing height rises above 5000 ft and remains above 5000 ft through the evening.

 

Transport wind WSW to WNW at 10 - 20 mph during the morning.  Transport wind increases to WSW to WNW at 15 - 25 mph during the afternoon and increases to WNW to NW at 18 - 32 mph during the evening.

 

Surface wind SW to WNW at 5 - 9 mph during the morning.  Surface wind shifts to S to SW and increases to 9 - 15 mph during the afternoon then shifts to WNW to NW at 10 - 20 mph during the evening.

 

Zone 637, 643, 645, 646, and 644 East of R34E:

Mixing height below 3000 ft early rising to 3500 - 4500 ft by late morning.  Afternoon mixing height rises above 5000 ft and remains above 5000 ft through the evening.

 

Transport wind WSW to WNW at 10 - 16 mph during the morning.  Transport wind increases to WSW to WNW at 12 - 22 mph during the afternoon and increases to WNW to NW at 16 - 30 mph during the evening.

 

Surface wind SW to WNW at 5 - 9 mph.

 

OUTLOOK:

 

SATURDAY

Mixing height 3800 to 4800 ft during the morning rising above 5000 ft during the afternoon.  Transport wind WSW to WNW at 18 - 32 mph during the morning becoming W to NW at 22 - 38 mph during the afternoon.  Surface wind WSW to WNW at 10 - 18 mph.

 

SUNDAY

Mixing height 3200 to 4200 ft during the morning rising above 5000 ft during the afternoon.  Transport wind NW to N at 10 - 16 mph.  Surface wind NW to NNW at 8 - 12 mph.

 

MONDAY

Mixing height 3200 to 4200 ft during the morning rising above 5000 ft during the afternoon.  Transport wind NW to N at 6 - 10 mph.  Surface wind NW to NNE at 4 - 8 mph.

 

3.  BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646

    - Valid for burning done Friday, May 15, 2026.

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

 

Zone 640, 642, and 644 West of R35E:

Follow standard guidance matrix - see section 5 below - for burning units to the WSW through NW of SSRAs.  No additional restrictions necessary. 

 

Zone 637, 643, 645, 646, and 644 East of R34E:

Follow standard guidance matrix - see section 5 below - for burning units to the WSW through NNW of SSRAs.  No additional restrictions necessary. 

 

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

4.  SPECIAL NOTE:

 

    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

 

    The smoke management forecaster is available at (503)-

    945-7401. Please call this number and not individual's

    numbers to discuss daily burning.  For large burns (over

    2000 tons) or burns extending over a considerable period,

    please request a special forecast.  Avoid calling

    between 1:30 to 2:45 p.m.

 

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

    Daily/neo.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.