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

Thu Dec 9 14:36:33 PST 2010

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Thursday, December 9, 2010       2:30 PM      Pete Parsons

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

FRIDAY

A strong westerly flow aloft will continue to circulate bands of showers across western Oregon.  The air mass will begin to stabilize in the afternoon, as the upper-level winds veer to northwesterly. Showers will briefly taper off in the evening.  West-southwesterly transport winds will also decrease in the evening.  Smoke dispersal conditions should remain fair to good during the day, but mixing heights will drop sharply in the evening.

OUTLOOK (SATURDAY-MONDAY)
A strong warm front will spread significant rainfall, from south to north, across western Oregon early Saturday morning.  Rain could become heavy by late-morning, with the main area of rain shifting to over the northern zones in the afternoon.  The snow level will start out near 4000 feet north and 6000 feet south but rapidly rise to 6000 feet north and to above 8000 feet south in the afternoon.

The combination of locally heavy rainfall and rising snow levels may lead to areas of flooding, especially along the northern coastal rivers.  Increasing south to southeasterly transport winds will turn south-southwesterly on the south side of the warm front, across the southern zones, in the afternoon.  North of the warm front, smoke dispersal conditions will likely be marginal to poor.  South of the warm front, across the southwestern zones, warmer surface winds will promote better afternoon mixing with fair smoke dispersion.

The strong warm front should push north of the state by Sunday morning, with the rainfall tapering off.  Sunday should be mostly dry with the freezing level rising to near 10,000 feet.  South to southwesterly winds will make for unseasonably mild conditions with some clearing.  Smoke dispersion should be fair.

The break from the wet weather will be short-lived, with the cold front forecast to come onshore Monday morning and spread rain back across the region by Monday afternoon.  Snow levels will remain quite high early and then drop to around 6000 feet north and 7000 feet south by evening.  Smoke dispersal conditions will improve to fair to good with continued south to southwesterly transport winds.

2.  DISPERSION

Zone 601, 602, 603, 612 and 615-620 (North and South Coast Range):

MORNING

Mixing height 3000 - 4000 ft.

Transport wind WSW at 18 - 32 mph.

Surface wind SSW to WSW at 8 - 12 mph.

AFTERNOON

Mixing height 3300 - 4300 ft.

Transport wind decreases to WSW to WNW at 12 - 22 mph.

Surface wind SW to WNW at 5 - 9 mph.

EVENING

Mixing height 1000 - 1500 ft.

Transport wind shifts to S to SW and decreases to 6 - 10 mph.

Surface wind becomes light and variable but favors S to SW and controlled by local terrain.

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

MORNING

Mixing height 3000 - 4000 ft.

Transport wind WSW at 18 - 32 mph.

Surface wind SW to WSW at 10 - 16 mph.

AFTERNOON

Mixing height 3700 - 4700 ft.

Transport wind WSW to WNW at 15 - 25 mph.

Surface wind SW to WNW at 6 - 12 mph.

EVENING

Mixing height 1000 - 2000 ft.

Transport wind decreases to SSW to WSW at 8 - 12 mph.

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

OUTLOOK:

SATURDAY

In the north mixing height below 1000 ft early rising to 1200 to 2200 ft by late morning and through the afternoon.  In the south mixing height below 1000 ft early rising to 1700 to 2700 ft by late morning rising to 3300 to 4300 ft during the afternoon.  Transport wind SSE to SSW at 10 - 22 mph during the morning becoming SSW to SW at 20 - 36 mph during the afternoon.  Surface wind SE to S at 6 - 10 mph during the morning becoming S to SW at 10 - 18 mph during the afternoon.

SUNDAY

Mixing height 2800 to 3800 ft throughout the day.  Transport wind SSW to SW at 15 - 29 mph.  Surface wind SE to SSW at 4 - 8 mph.

MONDAY

Mixing height 1800 to 2800 ft during the morning rising to 4000 to 5000 ft during the afternoon.  Transport wind SSW to SW at 20 - 34 mph.  Surface wind SSE to SSW at 10 - 16 mph.

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

These instructions are valid for burning conducted on Friday, December 10, 2010.

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

Coast Range

Zone 601, 612, and 616 east of R9W

Units should be 750 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.  North of Tillamook in Zone 601, use standard guidance matrix. (See section 5 below.)  Higher tonnage is possible south of T29S in Zone 616.  Call the forecaster.

Zone 602 and 603

Units should be 300 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.  North of T3N in Zone 602, use standard guidance matrix. (See section 5 below.)  Units may be 750 tons or less, spaced 10 miles apart, south of the Siuslaw River in Zone 603.

Zone 615 and 616 west of R8W

Units should be 1000 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.  Higher tonnage is possible south of T29S in Zone 616.  Call the forecaster.

Zone 618

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

Zone 619

Units should be 1500 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.

Zone 620

Units should be 500 tons or less, spaced 10 miles apart, and 12 miles from downwind SSRAs.  Higher tonnage is possible south of T35S.  Call the forecaster.

Cascades

All zones except Zone 610 and 611

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

Zone 610 and 611

Units should be 1000 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.

Siskiyous

Units should be 1000 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.

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

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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