SMI West (Smoke Management Instructions) Western Oregon Smoke Management Instructions

Sat May 21 14:31:54 PDT 2011

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Saturday, May 21, 2011       2:30 PM      Pete Parsons

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

SUNDAY

An upper-level trough is forecast to extend from the Gulf of Alaska southeastward to over the Pacific Northwest. The second in a series of embedded weather disturbances will rotate onshore during the day.  That will maintain strong onshore flow, mostly cloudy skies, and a chance of light showers, mainly north and over higher terrain.

Rainfall totals should generally be less than one-tenth of an inch north, with only widely scattered showers south.  High temperatures will likely be as much as 10 degrees below normal, with continued northwesterly transport winds.  The snow level will drop to around 5000 feet north and 6000 feet south, with cool air aloft leading to fair to good afternoon mixing.

OUTLOOK (MONDAY-WEDNESDAY)

A moderately strong upper-level trough will rotate another embedded weather disturbance onshore Monday.  This system looks to be a little stronger than the previous two, with generally cloudy skies and scattered showers expected across all zones.  Rainfall totals will likely range from a few hundredths to around one-tenth of an inch, with the snow level dropping to near 4500 feet.  High temperatures should remain about 6-10 degrees below normal with northwesterly transport winds.  Daytime mixing will be fair to good.

The upper-level trough is forecast to weaken by Tuesday, as it moves off to the east.  A weak and transitory upper-level ridge will slowly clear skies, as high temperatures return to within 5 degrees of normal. Daytime mixing will remain fair to good, but onshore transport winds will become light.

An impressive upper-level trough is forecast to approach the coastline on Wednesday, as a strengthening southwesterly jet stream directs an active cold front across the state.  Measureable precipitation is likely for all zones with more than one-quarter of an inch locally possible.  Temperatures will drop back below normal, with the snow level lowering to near 4000 feet late.  Increasing southwesterly transport winds will make for fair to good smoke dispersal conditions.

2.  DISPERSION

Zone 601-612 (North Coast Range and Cascades):

MORNING

Mixing height below 1000 ft early rising to 3000 - 4000 ft by late morning.

Transport wind WSW to WNW 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 W to NW at 8 - 12 mph.

Surface wind increases to W to NW at 6 - 10 mph.

EVENING

Mixing height 1700 - 2700 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

Zone 615-623 (South Coast Range and Cascades):

MORNING

Mixing height below 1000 ft early rising to 3000 - 4000 ft by late morning.

Transport wind NW to N at 4 - 8 mph.

Surface wind NW to N at 4 - 8 mph.

AFTERNOON

Mixing height rising above 5000 ft.

Transport wind increases to NW to NNW at 10 - 18 mph.

Surface wind increases to NW to NNW at 9 - 15 mph.

EVENING

Mixing height 1700 - 2700 ft.

Transport wind NW to N at 8 - 12 mph.

Surface wind NW to N at 5 - 9 mph.

OUTLOOK:

MONDAY

Mixing height below 1000 ft early rising to 3200 to 4200 ft by late morning rising above 5000 ft during the afternoon.  Transport wind light and variable during the morning becoming W to NW at 10 - 16 mph during the afternoon.  Surface wind light and variable during the morning becoming W to NNW at 6 - 12 mph during the afternoon.

TUESDAY

Mixing height below 1000 ft early rising to 2100 to 3100 ft by late morning rising to 4200 to 5000 ft during the afternoon.  Transport wind light and variable.  Surface wind light and variable.

WEDNESDAY

Mixing height below 1000 ft early rising to 2200 to 3200 ft by late morning rising above 5000 ft during the afternoon.  Transport wind S to SW at 8 - 12 mph during the morning becoming SSW to SW at 14 - 28 mph during the afternoon.  Surface wind S to SW at 4 - 8 mph during the morning becoming SSW to WSW at 8 - 14 mph during the afternoon.

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

These instructions are valid for burning conducted on Sunday, May 22, 2011.

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

Coast Range

Zone 601 and 612

Units should be 1000 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  Restrict units in or near corridors to 500 tons or less.

Zone 602, 603, and 620

Units should be 500 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  Avoid burning in or near corridors.  Higher tonnage is possible south of the Siuslaw River in Zone 603.  Call the forecaster.  Higher tonnage is possible south of the Rogue River in Zone 620.  Call the forecaster.

Zone 615, 618, and 619

Use standard guidance matrix. (See section 5 below.)  Avoid burning directly upwind of the North Bend/Coos Bay SSRA.

Zone 616 west of R8W

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

Zone 616 east of R9W

Units should be 750 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  Restrict units to 500 tons or less south of T30S.

Cascades

Zone 605, 606, 607, 608, 609, 616, 617, 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.  South of T30S in Zone 616 units should be 500 tons or less, spaced 5 miles apart.

Zone 610 and 611

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

Zone 620 and 622

Units should be 500 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  East of R2W in Zone 622, use standard guidance matrix. (See section 5 below.)

Siskiyous

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

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

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://oregon.gov/ODF/FIRE/fire.shtml/#Smoke_Management

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

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

5.  STANDARD GUIDANCE MATRIX:

  * Greater than 5000 ft mixing height:  No burning within 5 miles of

    downwind SSRA.  Maximum 100 tons per mile from downwind SSRA.

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

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

    downwind SSRA.  Maximum 75 tons per mile from downwind SSRA.

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

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

    downwind SSRA.  Maximum 50 tons per mile from downwind SSRA.

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

  * All exceptions must be coordinated with the duty forecaster

    prior to ignition.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://omls.oregon.gov/pipermail/smi_west/attachments/20110521/a70034de/attachment.html>