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

Wed May 18 14:34:05 PDT 2011

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Wednesday, May 18, 2011       2:30 PM      Pete Parsons

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

THURSDAY

The upper-level trough that has been bringing cool and damp conditions to the region for the past several days will continue to weaken and drift southeastward. It is forecast to stretch from South Dakota to southern California by the afternoon.  Meanwhile, a weak ridge of high pressure will build just offshore and turn the flow aloft north-northwesterly over Oregon.  Continued drying and warming of the air mass will lift the freezing level to 8-9000 feet.

After a chilly early morning, ample afternoon sunshine should warm maximum temperatures to near or slightly above average. It will still be cool enough aloft for fair to good daytime mixing.  Transport winds may be northeasterly, in the morning, across the southern zones, which could provide some coastal-zones burning opportunities.  Look for northerly transport winds in the northern zones.  Transport winds should become northwesterly across the northern zones and north to northwesterly across the southern zones by the afternoon.

OUTLOOK (FRIDAY-SUNDAY)

The upper-level ridge axis is forecast to move onshore Friday morning and slowly drift eastward, to near to Idaho border, by evening.  Light morning transport winds should increase from the northwest during the late-morning and afternoon.  Maximum temperatures will be 5 to 10 degrees above average, which should lift afternoon mixing heights above 4000 feet.

On Saturday a weak upper-level trough is forecast to come onshore, along with a surface cold front.  That should bring a return of mostly cloudy skies with at least a chance of a few showers, mainly over higher terrain.  Maximum temperatures will likely drop back to near or slightly below normal, with increasing northwesterly transport winds.  Cooling aloft will promote fair to good afternoon mixing.

Little change in the weather pattern is forecast for Sunday, with westerly flow aloft maintaining onshore flow, mostly cloudy skies, and a chance of a few showers.  Temperatures will hover near normal with fair to good afternoon mixing and northwesterly transport winds.

2.  DISPERSION

All Zones:

MORNING

Mixing height below 1000 ft early rising to 2500 - 3500 ft by late morning.

Transport wind NNW to NNE at 5 - 9 mph.

Surface wind NNW to NNE at 4 - 8 mph.

AFTERNOON

Mixing height rising to 4000 - 5000 ft.

Transport wind NNW to NNE at 8 - 12 mph.

Surface wind NW to N at 6 - 10 mph.

EVENING

Mixing height 2500 - 3500 ft.

Transport wind similar to afternoon.

Surface wind similar to afternoon.

OUTLOOK:

FRIDAY

Mixing height below 1000 ft early rising to 2600 to 3600 ft by late morning rising to 4200 to 5000 ft during the afternoon.  Transport wind light and variable during the morning becoming WNW to NNW at 6 - 12 mph during the afternoon.  Surface wind light and variable during the morning becoming WNW to NNW at 6 - 12 mph during the afternoon.

SATURDAY

Mixing height below 1000 ft early rising to 2600 to 3600 ft by late morning rising to 4100 to 5000 ft during the afternoon.  Transport wind WNW to NNW at 4 - 8 mph.  Surface wind WNW to NNW at 4 - 8 mph.

SUNDAY

Mixing height below 1000 ft early rising to 2500 to 3500 ft by late morning rising above 5000 ft during the afternoon.  Transport wind NW to N at 5 - 9 mph.  Surface wind NW to N at 4 - 8 mph.

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

These instructions are valid for burning conducted on Thursday, May 19, 2011.

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

Coast Range

Zone 601 and 612

Units should be 1500 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Higher tonnage is possible south of Waldport in Zone 612.  Call the forecaster.

Zone 602 and 603

Units should be 750 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Avoid ignitions north of Forest Grove/Hillsboro or Sheridan/Willamina in Zone 602.  Higher tonnage is possible south of T17S in Zone 603.  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.

Zone 620

Units should be 500 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  Higher tonnage is possible south of the Rogue River.  Call the forecaster.

Cascades

Zone 605, 606, and 610

Units should be 1000 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.  Verify transport winds away from SSRA if burning within 10 miles of the SSRA in Zone 605 and 606.

Zone 607, 608, 609, 611, 617, and 623

Use standard guidance matrix. (See section 5 below.)  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  South of T30S in Zone 617 units should be 750 tons or less, spaced 5 miles apart.

Zone 616

Units should be 1200 tons or less, spaced 5 miles apart, and 10 miles from downwind SSRAs.  South of T30S units should be 500 tons or less, spaced 5 miles apart.

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.)

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

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/20110518/ee40fdd2/attachment.html>