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

Tue Nov 17 14:26:53 PST 2009

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS
SALEM FORESTRY WEATHER CENTER
OREGON DEPARTMENT OF FORESTRY

ISSUED: Tuesday, November 17, 2009       2:30 PM      Jim Little

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

A Deep upper level trough in the northern Gulf of Alaska continues to influence Pacific Northwest weather through the rest of the week.  Weather systems spin around the bottom of this feature through Saturday.  Computer models show a surge of moisture during the morning over most of western Oregon, then some drying in the afternoon.  Rainfall totals should be light.  Mixing heights will be generally favorable for good smoke dispersal and transport winds mostly southerly.

    OUTLOOK (THURSDAY-SATURDAY)

A stronger system than the one for Wednesday stalls along the coast on Thursday.  The pattern is similar to the pattern for Monday and Tuesday but likely winds will not be as strong.  Models have been a bit inconsistent on exactly where this system stalls a 100 mile error in positioning means the difference in heavy rain or not much rain at all.  Thus low confidence in forecast for Thursday.  The front should drag through during the day on Friday.  Mixing heights may be suppressed with warm overrunning aloft on Thursday but should be 5000 feet or better on Friday.   On Saturday a warm front moves through for additional rain but smoke dispersal conditions should remain fair.

2.  DISPERSION

Zone 601, 602, 603 and 612 (North Coast Range):

MORNING
Mixing height 2600 - 3600 ft.
Transport wind S to SSW at 12 - 22 mph.
Surface wind SSE to SSW at 8 - 14 mph.

AFTERNOON
Mixing height rising above 5000 ft.
Transport wind SSW at 24 - 42 mph.
Surface wind increases to S to SW at 15 - 25 mph.

EVENING
Mixing height remains above 5000 ft.
Transport wind SSW at 29 - 49 mph.
Surface wind S to SSW at 18 - 30 mph.

Zone 605-611 (North Cascades):

MORNING
Mixing height 2300 - 3300 ft.
Transport wind SSE to SSW at 10 - 20 mph.
Surface wind SSE to SSW at 10 - 18 mph.

AFTERNOON
Mixing height rising to 4000 - 5000 ft.
Transport wind increases to S to SW at 14 - 28 mph.
Surface wind S to SW at 13 - 25 mph.

EVENING
Mixing height 3400 - 4400 ft.
Transport wind SSW at 18 - 32 mph.
Surface wind S to SSW at 16 - 30 mph.

Zone 615-620 (South Coast Range):

MORNING
Mixing height 2200 - 3200 ft.
Transport wind S to SW at 9 - 15 mph.
Surface wind S to SW at 8 - 12 mph.

AFTERNOON
Mixing height rising above 5000 ft.
Transport wind increases to SSW to SW at 15 - 25 mph.
Surface wind increases to SSW to SW at 10 - 22 mph.

EVENING
Mixing height 4200 - 5000 ft.
Transport wind S to SSW at 15 - 25 mph.
Surface wind SSE to SSW at 10 - 20 mph.

Zone 616-623 (South Cascades):

MORNING
Mixing height 1800 - 2800 ft.
Transport wind SSE to SW at 6 - 12 mph.
Surface wind SSE to SSW at 6 - 12 mph.

AFTERNOON
Mixing height rising to 3000 - 4000 ft.
Transport wind increases to SSW to SW at 10 - 22 mph.
Surface wind S to SW at 10 - 16 mph.

EVENING
Mixing height 2700 - 3700 ft.
Transport wind S to SW at 10 - 18 mph.
Surface wind SSE to SSW at 8 - 12 mph.

OUTLOOK:

THURSDAY
Mixing height 4000 to 5000 ft throughout the day.  Transport wind S to SSW at 16 - 30 mph.  Surface wind S to SSW at 12 - 24 mph.

FRIDAY
Mixing height 2500 to 3500 ft during the morning rising above 5000 ft during the afternoon.  Transport wind S to SSW at 16 - 30 mph during the morning becoming W to NW at 10 - 18 mph during the afternoon.  Surface wind light and variable.

SATURDAY
Mixing height 2200 to 3200 ft during the morning rising to 4200 to 5000 ft during the afternoon.  Transport wind SSW to SW at 9 - 15 mph during the morning becoming S to SSW at 13 - 25 mph during the afternoon.  Surface wind S to SW at 4 - 8 mph.

3.  BURNING INSTRUCTIONS FOR ALL ZONES IN THE WESTERN OREGON AREA
These instructions are valid for burning conducted on Wednesday, November 18, 2009.
=================================================================

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 611
Use standard guidance matrix. (See section 5 below.)  Ensure adequate distance from downwind SSRAs for smoke to dissipate.  Verify transport winds away from SSRA if burning within 10 miles of the SSRA in Zone 605 and 606.  Avoid ignitions north of T24S in Zone 616.

Zone 611
Units should be 1000 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.

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

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://omls.oregon.gov/pipermail/smi_west/attachments/20091117/487453a5/attachment.html>