SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Saturday, April 25, 2015       2:30 PM      Tom Jenkins

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Oregon Department of Forestry’s Weather Center will resume 7-days-per-week operations to support the Spring 2015 Prescribed Burning Season on Sunday, April 19th 2015. We have also resumed issuing a daily Smoke Management Forecast and Instructions for the entire state until further notice.

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

 

SHORT-TERM DISCUSSION

The atmosphere will stabilize rapidly, as an upper-level ridge builds offshore Oregon Saturday night and early Sunday morning. Onshore flow will persist across all zones, with poor mixing in the morning that improves steadily after sunrise. Northwest zones may see light rain after sunset as a weakening Warm Front moves ashore near the mouth of the Columbia River. The atmosphere will continue to stabilize further Sunday evening.

EXTENDED DISCUSSION

The upper-level ridge builds and begins to tilt eastward as it moves over the Oregon coast Monday morning. Poor mixing conditions in the morning with light winds will create an inversion in sheltered valleys. Warming air aloft will restrict the amount of mixing in the atmosphere Monday afternoon. The upper-level ridge will shift into the Cascades Monday evening, leaving a weak surface ridge in Willamette Valley for another night of stable weather. Tuesday morning, a stronger inversion will keep mixing levels low, with gradual improvement after sunrise. The surface ridge will enter the Cascades Tuesday afternoon, shifting winds to offshore flow. An upper-level trough will approach the Pacific Northwest after sunset Tuesday evening. Wednesday morning, a weak surface trough will pass through northwestern zones. This feature will enhance onshore flow and mixing as it approaches. Elsewhere, the surface ridge will keep the atmosphere stable with offshore flow and another day of limited mixing conditions.

2.  DISPERSION

 

SUNDAY

 

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

 

MORNING

Mixing height below 1000 ft early rising to 3800 - 4800 ft by late morning.

Transport wind SE to S at 8 - 12 mph.

Surface wind SSE to SSW at 5 - 9 mph.

 

AFTERNOON

Mixing height above 5000 ft.

Transport wind S to SW at 10 - 20 mph.

Surface wind S to SW at 5 - 9 mph.

 

EVENING

Mixing height lowers below 1500 ft after sunset.

Transport wind shifts to SW to W at 8 - 12 mph.

Surface wind similar to afternoon.

 

Zone 605-611 and 639 (North Cascades):

 

MORNING

Mixing height below 1000 ft early rising to 4000 - 5000 ft by late morning.

Transport wind S to SW at 5 - 9 mph.

Surface wind ESE to S at 4 - 8 mph.

 

AFTERNOON

Mixing height above 5000 ft.

Transport wind shifts to WSW to WNW at 8 - 12 mph.

Surface wind shifts to SW to W at 5 - 9 mph.

 

EVENING

Mixing height lowers below 1000 ft after sunset.

Transport wind similar to afternoon.

Surface wind WSW to NW at 4 - 8 mph.

 

Zone 615-620 (South Coast Range):

 

MORNING

Mixing height below 1500 ft early rising to 3500 - 4500 ft by late morning.

Transport wind S to SW at 4 - 8 mph.

Surface wind E to SE at 4 - 8 mph.

 

AFTERNOON

Mixing height rising above 5000 ft.

Transport wind SSW to WSW at 5 - 9 mph.

Surface wind SE to S at 4 - 8 mph.

 

EVENING

Mixing height lowers below 1000 ft after sunset.

Transport wind shifts to NNE to NE at 8 - 12 mph.

Surface wind shifts to NW to N at 4 - 8 mph.

 

Zone 616-623 (South Cascades):

 

MORNING

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

Transport wind S to SW at 4 - 8 mph.

Surface wind light and variable but favors W and controlled by local terrain.

 

AFTERNOON

Mixing height rising above 5000 ft.

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

Surface wind increases to W to NW at 5 - 9 mph.

 

EVENING

Mixing height lowers below 2000 ft after sunset.

Transport wind shifts to NNW to NNE at 8 - 12 mph.

Surface wind NW to N at 4 - 8 mph.

 

OUTLOOK:

 

MONDAY

In the north mixing height below 1000 ft early rising to 1800 to 2800 ft by late morning rising to 3200 to 4200 ft during the afternoon.  In the south mixing height below 1000 ft early rising to 1000 to 1800 ft by late morning rising to 3200 to 4200 ft during the afternoon.  Transport wind E to SE at 4 - 8 mph during the morning becoming SE to S at 6 - 10 mph during the afternoon.  Surface wind E to SE at 4 - 8 mph during the morning becoming W to NW at 5 - 9 mph during the afternoon.

 

TUESDAY

Mixing height below 1000 ft early rising to 2500 to 3500 ft by late morning rising to 4200 to 5000 ft during the afternoon.  Transport wind SSW to WSW at 10 - 16 mph during the morning becoming SW to W at 14 - 28 mph during the afternoon.  Surface wind S to SW at 6 - 10 mph during the morning becoming SW to W at 10 - 18 mph during the afternoon.

 

WEDNESDAY

Mixing height below 1000 ft early rising to 2600 to 3600 ft by late morning rising above 5000 ft during the afternoon.  Transport wind NW to NNE at 6 - 10 mph during the morning becoming NW to NNW at 10 - 16 mph during the afternoon.  Surface wind WNW to NNW at 6 - 10 mph.

 

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

These instructions are valid for burning conducted on Sunday, April 26, 2015.

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Coast Range

 

Zone 601, 612, 615, and 620

Units should be 1500 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  North of Tillamook in Zone 601, use standard guidance matrix. (See section 5 below.)  South of T35S in Zone 620 units should be 500 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.

 

Zone 602, 603, and 616 east of R9W

Units should be 750 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  North of T3N in Zone 602, use standard guidance matrix. (See section 5 below.)  Higher tonnage is possible south of T29S in Zone 616.  Call the forecaster.

 

Zone 616 west of R8W

Units should be 1200 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  Higher tonnage is possible south of T29S.  Call the forecaster.

 

Zone 618

Use standard guidance matrix. (See section 5 below.)

 

Zone 619

Units should be 2000 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.

 

 

Cascades

 

Zone 605, 606, 607, 608, 639, 616, 617, 622, and 623

Use standard guidance matrix. (See section 5 below.)  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  From T15S through T20S in Zone 608 units should be 1000 tons or less, spaced 5 miles apart.

 

Zone 610, 611, and 620

Units should be 1000 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.

 

 

Siskiyous

Units should be 1500 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.

 

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4.  SPECIAL NOTE:

 

    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 he will return your call as soon as possible.

    Avoid calling between 2 to 2:30 p.m. 

 

    The forecast is available on the Internet at:

      http://www.oregon.gov/ODF/Pages/FIRE/fire.aspx#Smoke_Management_Information

 

    Please ensure your units have been planned and accomplished by checking:

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

 

    The forecast/instruction telephone recording is: (503) 945-7400.

 

    Submit feedback at: http://weather.smkmgt.com/feedback.

 

    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:  No burning within 5 miles of

    downwind SSRA.  Limit to 100 tons per mile from downwind SSRA.

    Example:  500 tons allowed if burned 5 miles from downwind SSRA.

 

  * 3000 - 5000 ft mixing height:  No burning within 10 miles of

    downwind SSRA.  Limit to 75 tons per mile from downwind SSRA.

    Example:  750 tons allowed if burned 10 miles from downwind SSRA.

 

  * Less than 3000 ft mixing height:  No burning within 15 miles of

    downwind SSRA.  Limit to 50 tons per mile from downwind SSRA.

    Example:  750 tons allowed if burned 15 miles from downwind SSRA.

 

  * 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.