SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Monday, May 13, 2024       2:30 PM      Pete Parsons

 

******************** Instruction Zones Update ***********************

The National Weather Service is changing borders and numbering of their fire zones.  ODF will use the previous zone boundaries for smoke management and not change with the updates.

A link to ODF’s smoke forecast zones is at the bottom of the instructions in the Special Notes section. (https://www.oregon.gov/odf/fire/documents/smoke-forecast-zone-map.pdf)

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

 

SHORT-TERM DISCUSSION

A dry upper-level trough increased the onshore flow today, which cooled temperatures about 5-10°F from Sunday.  However, skies remain generally clear, except for some clouds along the coast.  Good mixing and NW transport winds allowed for considerable burning of units in central Oregon.

High pressure will build back over the region on Tuesday with continued NW flow aloft and NW-N winds at the surface.  The coast and NW interior will see some brief morning marine clouds, otherwise expect sunny skies.  Temperatures will remain about 5-10°F above average with good daytime mixing over the coastal range and excellent mixing over the Cascades and in central Oregon.

EXTENDED DISCUSSION

An upper-level ridge strengthens on Wednesday, warming temperatures to 10-15°F above average under sunny skies.  Daytime mixing will remain better from the Cascades to central Oregon than over the coastal range with continued NW-N surface and transport winds.

The upper-level ridge flattens on Thursday in response to a trough dropping SE from the northern Gulf of Alaska.  NW winds will increase across all zones in the afternoon with some clouds making it to the extreme NW zones.  Temperatures may cool a few degrees in NW Oregon, while holding fast or warming slightly across the south and east.  Mixing will be better over the Cascades and central Oregon than over the coastal zones.

Friday will bring some clouds to the northern zones, where the threat of a light shower can’t be ruled out.  Southern zones should remain sunny.  All areas will see several degrees of cooling with brisk NW winds across the northern zones veering to NW-N across the southern zones.  Mixing will be excellent, especially in the north.

2.  DISPERSION

 

TUESDAY

 

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

 

MORNING

Mixing height below 1000 ft early rising to 2000 - 3000 ft by late morning.

Transport wind NNW to NNE at 6 - 12 mph.

Surface wind NNW to NNE at 5 - 9 mph.

 

AFTERNOON

Mixing height 3000 - 4000 ft.

Transport wind NNW to NNE at 9 - 15 mph.

Surface wind similar to morning.

 

EVENING

Mixing height 1500 - 2500 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

 

Zone 605-611, 639 and 616-623 (North and South Cascades):

 

MORNING

Mixing height below 1000 ft early rising to 2700 - 3700 ft by late morning.

Transport wind NW to NNE at 6 - 10 mph.

Surface wind NW to NNE at 4 - 8 mph.

 

AFTERNOON

Mixing height rising above 5000 ft.

Transport wind similar to morning.

Surface wind similar to morning.

 

EVENING

Mixing height 2000 - 3000 ft.

Transport wind NNW to NNE at 10 - 18 mph.

Surface wind NNW to NNE at 8 - 12 mph.

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height below 1000 ft early rising to 2000 - 3000 ft by late morning.

Transport wind NNE to NE at 8 - 12 mph.

Surface wind N to NE at 6 - 10 mph.

 

AFTERNOON

Mixing height 2800 - 3800 ft.

Transport wind N to NE at 10 - 20 mph.

Surface wind NNW to NNE at 9 - 15 mph.

 

EVENING

Mixing height 1500 - 2500 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

 

OUTLOOK:

 

WEDNESDAY

Mixing height below 1000 ft early rising to 2100 to 3100 ft by late morning rising to 3600 to 4600 ft during the afternoon.  Transport wind NNW to NE at 6 - 10 mph.  Surface wind NNW to NNE at 4 - 8 mph.

 

THURSDAY

Mixing height below 1000 ft early rising to 2300 to 3300 ft by late morning rising to 3800 to 4800 ft during the afternoon.  Transport wind NW to N at 6 - 10 mph during the morning becoming NW to N at 10 - 18 mph during the afternoon.  Surface wind NW to N at 4 - 8 mph.

 

FRIDAY

Mixing height 2700 to 3700 ft during the morning rising above 5000 ft during the afternoon.  Transport wind NW to NNW at 10 - 22 mph during the morning becoming NW to NNW at 14 - 28 mph during the afternoon.  Surface wind NW to NNW at 10 - 16 mph.

 

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

    - Valid for burning done Tuesday, May 14, 2024.

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

 

Coast Range

 

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

 

Zone 601, 612, 615, 616 west of R8W, 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 600 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Limit tonnage north of Forest Grove/Hillsboro or Sheridan/Willamina in Zone 602.  Higher tonnage is possible south of T17S in Zone 603.  Call the forecaster.

 

Zone 616 east of R9W

Units should be 1200 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Restrict units to 500 tons or less south of T30S.

 

 

Cascades

 

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

 

Zone 605, 606, 607, 608, 639, 611, 616, 617, and 623

Use standard guidance matrix - see section 5 below.  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  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 1000 tons or less, spaced 3 miles apart.  South of T30S in Zone 617 units should be 1000 tons or less, spaced 3 miles apart.

 

Zone 610

Units should be 1200 tons or less, spaced 3 miles apart, and 5 miles from downwind SSRAs.

 

Zone 620 and 622

Units should be 750 tons or less, spaced 3 miles apart, and 5 miles from downwind SSRAs.

 

 

Siskiyous

 

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

 

Use standard guidance matrix - see section 5 below.

 

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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.