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

Sat May 7 14:31:39 PDT 2011

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Saturday, May 7, 2011       2:30 PM      Pete Parsons

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

-   Issued 7-days-a-week through the spring burning season -

SUNDAY

An unseasonably cold upper-level trough is forecast to move over the Pacific Northwest.  Rain and snow showers will be widespread with precipitation totals ranging from around one-tenth of an inch to more than one-quarter of an inch.  The snow level will drop to 3000-4000 feet with surface temperatures about 10 degrees below average.  Cold air aloft should make for good mixing with onshore transport winds veering to northwesterly.

OUTLOOK (MONDAY-WEDNESDAY)

On Monday, the upper-level trough is forecast to drop southeastward, to over Nevada, with a drier north-northeasterly flow aloft over Oregon.  Look for decreasing showers, with partial clearing.  Surface temperatures will remain well below normal, with minor warming aloft leading to slightly lower afternoon mixing heights.  Transport winds will turn mostly northerly.

Tuesday looks dry and significantly warmer, as a transitory upper-level ridge moves onshore and over Oregon.  Residual low-level moisture may lead to areas of brief morning valley fog or low clouds, with skies becoming mostly sunny.  After a chilly morning, with poor mixing, more surface heating will improve afternoon smoke dispersal conditions to fair to good.  Daytime highs should recover to near or slightly above normal.  Light mostly northerly morning transport winds will turn northwesterly in the afternoon.

The upper-level ridge is forecast to shift eastward, to over Idaho, by Wednesday morning, with an increasing southwesterly flow aloft over Oregon.  The latest computer guidance is forecasting a cold front to spread rain onshore, around midday, and across western Oregon by evening.  Ahead of the cold front, some sunshine should help temperatures warm to near normal north and above normal south.  Good mixing is expected for eastern zones, which will likely see some filtered sunshine, but mixing heights may be slightly suppressed by cloud-cover over the coast range.  Southwesterly morning transport winds should veer to more westerly by late-afternoon.  Afternoon rainfall amounts should range from one-tenth to one-quarter of an inch north with most southern zones picking up less than one-tenth of an inch.  The snow level will drop to about 4500 feet north and 5500 feet south late.

2.  DISPERSION

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

MORNING

Mixing height below 2000 ft early rising to 2500 - 3500 ft by late morning.

Transport wind WSW to WNW at 8 - 12 mph.

Surface wind WSW to NW at 4 - 8 mph.

AFTERNOON

Mixing height rising above 5000 ft.

Transport wind shifts to NW to NNW at 10 - 16 mph.

Surface wind W to NW at 6 - 10 mph.

EVENING

Mixing height 2500 - 3500 ft.

Transport wind WNW to NNW at 8 - 12 mph.

Surface wind WSW to WNW at 4 - 8 mph.

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

MORNING

Mixing height below 2000 ft early rising to 2500 - 3500 ft by late morning.

Transport wind WNW to NW at 8 - 12 mph.

Surface wind W to NW at 4 - 8 mph.

AFTERNOON

Mixing height rising above 5000 ft.

Transport wind NW to NNW at 10 - 20 mph.

Surface wind NW to NNW at 8 - 12 mph.

EVENING

Mixing height 2500 - 3500 ft.

Transport wind NW to N at 8 - 12 mph.

Surface wind NW to N at 4 - 8 mph.

OUTLOOK:

MONDAY

Mixing height 2000 to 3000 ft during the morning rising to 3800 to 4800 ft during the afternoon.  Transport wind WNW to NNW at 6 - 10 mph during the morning becoming NNW to N at 10 - 18 mph during the afternoon.  Surface wind W to NNW at 4 - 8 mph.

TUESDAY

Mixing height below 1000 ft early rising to 2000 to 3000 ft by late morning rising to 3600 to 4600 ft during the afternoon.  Transport wind NNW to NE at 4 - 8 mph during the morning becoming NW to N at 6 - 10 mph during the afternoon.  Surface wind light and variable during the morning becoming WNW to NNW at 4 - 8 mph during the afternoon.

WEDNESDAY

Mixing height below 1000 ft early rising to 2000 to 3000 ft by late morning rising to 4000 to 5000 ft during the afternoon.  Transport wind SSW to SW at 8 - 14 mph during the morning becoming WSW to W at 10 - 22 mph during the afternoon.  Surface wind SSW to WSW at 5 - 9 mph during the morning becoming W to NW at 6 - 10 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 8, 2011.

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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.  Higher tonnage is possible south of Waldport in Zone 612.  Call the forecaster.

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 T17S 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, 611, 616, 617, and 623

Use standard guidance matrix. (See section 5 below.)  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  From T12S through T17S 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

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.

Siskiyous

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

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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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