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

Wed Dec 15 14:37:15 PST 2010

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Wednesday, December 15, 2010       2:30 PM      Pete Parsons

Note:  With the wind-down in fall burning, this office will terminate the daily forecasts and instructions until the spring burning season begins.  Please coordinate with the weather forecast office, if you plan to do burning, while this product is not being issued.  As always, if you need forecaster assistance, or smoke clearance, please call the forecaster line at 503-945-7401 Monday through Friday from 7:30 a.m. until 5:00 p.m.

1.  DISCUSSION AND FORECAST FOR THE WESTERN OREGON AREA FORECAST ZONES

601-623

THURSDAY
A weak and transitory upper-level ridge will slide across Oregon during the day.  Slight warming aloft will stabilize the atmosphere with only a slight chance of showers, mainly over the mountains.  The snow level will lift to 2500 feet north and 3500 feet south in the afternoon.  Afternoon smoke dispersal conditions will be marginal to fair with transport winds backing to the SSE.

OUTLOOK (FRIDAY-SUNDAY)
The upper-level ridge is forecast to stall over eastern Oregon and western Idaho on Friday, as a strong upper-level trough develops about 1000 miles west of the Washington and Oregon coast.  Increasing low-level offshore flow will help delay the onset of moisture from a strengthening westerly flow aloft.  Smoke dispersal conditions will remain marginal to fair.  A strong frontal system will spread rain and mountain snow back across the region by Friday night with snow levels ranging from near 1500 feet north to around 3000 feet south.

A strong cold is forecast to bring rain, mountain snow, and brisk winds to much of western Oregon Saturday morning.  Transport winds should become mostly southerly by Saturday afternoon with a strong west-southwesterly jet stream directing vigorous showers, and possibly thunderstorms, onshore.  Snow levels will range from near 2500 feet north to 4000 feet south.  Smoke dispersal conditions should be fair to good.

By Sunday, the parent upper-level though is forecast to progress eastward, to about 600 miles off the coastline, and continue to circulate abundant moisture across Oregon. A strong southwesterly jet stream, extending from the southern Oregon coast to over central Idaho, will slowly sag southward, to over northern California.  That will put Oregon on the cold side of the jet stream, with snow levels dropping to 1500 feet north and 2500 feet south by Sunday evening.  Smoke dispersal conditions should remain fair to good with mostly south to southwesterly transport winds.

2.  DISPERSION

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

MORNING

Mixing height 1000 - 2000 ft.

Transport wind SE to S at 5 - 9 mph.

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

AFTERNOON

Mixing height rising to 2300 - 3300 ft.

Transport wind SE to S at 8 - 12 mph.

Surface wind similar to morning.

EVENING

Mixing height 1000 - 2000 ft.

Transport wind E to SE at 5 - 9 mph.

Surface wind increases to ENE to ESE at 4 - 8 mph.

Zone 615-620 (South Coast Range):

MORNING

Mixing height below 1000 ft.

Transport wind light and variable but favors SE to S and controlled by local terrain.

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

AFTERNOON

Mixing height rising to 2800 - 3800 ft.

Transport wind similar to morning.

Surface wind similar to morning.

EVENING

Mixing height 1000 - 2000 ft.

Transport wind SE to SSW at 4 - 8 mph.

Surface wind similar to afternoon.

Zone 616-623 (South Cascades):

MORNING

Mixing height below 1000 ft.

Transport wind E to SE at 4 - 8 mph.

Surface wind E to SE at 4 - 8 mph.

AFTERNOON

Mixing height rising to 2700 - 3700 ft.

Transport wind SE to S at 4 - 8 mph.

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

EVENING

Mixing height 1000 - 2000 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

OUTLOOK:

FRIDAY

Mixing height below 1000 ft early rising to 1700 to 2700 ft by late morning rising to 2300 to 3300 ft during the afternoon.  Transport wind ESE to SSE at 6 - 12 mph.  Surface wind E to SE at 4 - 8 mph.

SATURDAY

Mixing height 2600 to 3600 ft during the morning rising to 3500 to 4500 ft during the afternoon.  Transport wind S to SW at 12 - 24 mph.  Surface wind SE to SSW at 6 - 10 mph.

SUNDAY

Mixing height 2000 to 3000 ft during the morning rising to 3500 to 4500 ft during the afternoon.  Transport wind S to SW at 15 - 25 mph.  Surface wind SE to SSW at 6 - 10 mph during the morning becoming S to SW at 8 - 12 mph during the afternoon.

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

These instructions are valid for burning conducted on Thursday, December 16, 2010.

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

Coast Range

Zone 601, 602, 603, 612, 615, 618, 619, and 620

Use standard guidance matrix. (See section 5 below.)  Avoid burning directly upwind of coastal SSRAs.

Zone 616 west of R8W

Units should be 1500 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.  Higher tonnage is possible south of T29S.  Call the forecaster.

Zone 616 east of R9W

Units should be 750 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.  Higher tonnage is possible south of T29S.  Call the forecaster.

Cascades

Zone 605 and 606

Units should be 300 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.

Zone 607, 608, 617, 620, and 622

Units should be 1000 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.

Zone 609, 610, and 623

Use standard guidance matrix. (See section 5 below.)  Ensure adequate distance from downwind SSRAs for smoke to dissipate.

Zone 611 and 616

Units should be 750 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.  In zone 616 avoid ignitions north of T24S.  South of T29S higher tonnage is possible.  Call the forecaster.

Siskiyous

Units should be 750 tons or less, spaced 10 miles apart, and 12 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://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.

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