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

Sat Oct 23 14:24:22 PDT 2010

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Saturday, October 23, 2010       2:30 PM      Pete Parsons

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

SUNDAY

Wet and windy weather is in store for all of Oregon on Sunday.  A warm front will renew the steady rain across western Oregon tonight (Saturday night). The third, and strongest, in a series of cold fronts will come onshore early Sunday morning and sweep across the entire state by evening.  Rainfall totals from this system will likely range from around one inch to more than two inches across western Oregon, with the heaviest rain likely on western mountain slopes.

The low-pressure center is forecast to become quite intense but track well to the northwest, to near the northern tip of Vancouver Island, British Columbia, by Sunday night.  The trailing cold front will bring strong southerly winds to all of Oregon.  Gusts to 60 mph are possible for coastal areas, with sections of the coast range and higher elevations of the Cascades likely getting gusts over 50 mph.  Gusts to near 40 mph are likely across the inland valleys.  In the wake of the cold front, blustery winds will likely turn more southwesterly.  Showers will be frequent with a slight chance of thunderstorms.  Snow levels will rapidly drop, with accumulating snow likely, above 4000 feet north and 4500 feet south, Sunday night.  South-southwesterly transport winds and high mixing heights will provide good smoke dispersal conditions.

OUTLOOK (MONDAY-WEDNESDAY)

A strong westerly jet stream, aimed right at Oregon, will continue significant shower activity Monday and Tuesday, with additional snowfall likely above 4000 feet north and 4500 feet south.  Rain and mountain snow showers are forecast to taper off late Tuesday, as the flow aloft turns northwesterly and more stable.  A weak and transitory upper-level ridge should bring one dry day, on Wednesday, with warming aloft lowering mixing heights.  Smoke dispersal conditions should remain good on Monday and then deteriorate to fair on Tuesday and marginal on Wednesday.

2.  DISPERSION

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

MORNING

Mixing height above 5000 ft.

Transport wind WSW at 25 - 45 mph.

Surface wind SSW to WSW at 15 - 25 mph.

AFTERNOON

Mixing height above 5000 ft.

Transport wind WSW at 25 - 45 mph.

Surface wind similar to morning.

EVENING

Mixing height remains above 5000 ft.

Transport wind WSW at 23 - 41 mph.

Surface wind similar to afternoon.

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

MORNING

Mixing height above 5000 ft.

Transport wind WSW at 30 - 50 mph.

Surface wind SW to WSW at 15 - 25 mph.

AFTERNOON

Mixing height above 5000 ft.

Transport wind WSW at 25 - 45 mph.

Surface wind similar to morning.

EVENING

Mixing height 3500 - 4500 ft.

Transport wind WSW at 20 - 36 mph.

Surface wind similar to afternoon.

OUTLOOK:

MONDAY

Mixing height 4000 to 5000 ft during the morning rising above 5000 ft during the afternoon.  Transport wind WSW to W at 18 - 32 mph.  Surface wind SSW to WSW at 10 - 18 mph.

TUESDAY

Mixing height 2400 to 3400 ft during the morning rising to 3400 to 4400 ft during the afternoon.  Transport wind WSW to WNW at 10 - 16 mph during the morning becoming WSW to WNW at 6 - 10 mph during the afternoon.  Surface wind S to SW at 5 - 9 mph during the morning becoming light and variable during the afternoon.

WEDNESDAY

Mixing height below 1000 ft early rising to 1000 to 1800 ft by late morning rising to 2000 to 3000 ft during the afternoon.  Transport wind light and variable during the morning becoming SE to S at 6 - 10 mph during the afternoon.  Surface wind light and variable.

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

These instructions are valid for burning conducted on Sunday, October 24, 2010.

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

Coast Range

All Zones

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

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 5 miles apart, and 10 miles from downwind SSRAs.

Siskiyous

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

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

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/20101023/1ecc7a11/attachment.html>