SMI South Central (Smoke Management Instructions) South Central Smoke Management Instructions

[ODF Smoke Management Instructions]

SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY



ISSUED: Friday, February 11, 2011       2:40 PM      Pete Parsons



1.  DISCUSSION AND FORECAST FOR SOUTH CENTRAL OREGON ZONES 624 AND 625


SATURDAY

The broad upper-level ridge that has been over the region for several days will flatten with increasing westerly flow aloft.  Skies will turn mostly cloudy, with a Pacific cold front spreading rain across western Oregon during the afternoon and evening. Ahead of the cold front, increasing low-level southwesterly winds will improve mixing with fair to good smoke dispersal conditions.
OUTLOOK (SUNDAY-TUESDAY)
The cold front will likely stall over central and southern Oregon Sunday morning, before migrating back northward, as a warm front, Sunday afternoon.  That will bring at least a slight chance of rain with continued mostly cloudy skies.  The snow level should remain above 6000 feet.  Smoke dispersal conditions should be fair with weakening low-level turning more southerly.

With the upper-level flow backing from westerly to southwesterly, most of the precipitation should push into Washington by Monday morning. Expect some partial clearing early with increasing mainly southerly transport winds.  Smoke dispersal conditions should be fair to good.
A strong upper-level trough will approach the coastline Monday afternoon with increasing southwesterly flow aloft.  The associated cold front should bring brisk south winds, with a good chance of rain by late in the day.  Snow dispersion will be fair to good.  Snow levels will stay in the 5-6000 foot range.
The strong cold front is forecast to move across the Cascades and into south-central Oregon Tuesday morning, bringing a significant and long-lasting change to the weather over the region.  Expect a period of steady rain that will change to snow, in the wake of the cold front, Tuesday afternoon. Smoke dispersal conditions should be good with southwesterly transport winds. Look for periods of snow to continue Tuesday night and Wednesday with accumulations likely.

2.  DISPERSION



SATURDAY

Mixing height below 500 ft early rising to 2000 - 3000 ft by late morning.  Afternoon mixing height rises to 3300 - 4300 ft then lowers to 2500 - 3500 ft during the evening.



Transport wind SSW to SW at 18 - 32 mph during the morning.  Transport wind increases to SSW to WSW at 26 - 46 mph during the afternoon and evening.



Surface wind SSE to SSW at 9 - 15 mph.



OUTLOOK:



SUNDAY

Mixing height 2200 - 3200 ft during the morning rising to 3000 - 4000 ft during the afternoon.  Transport wind SSW to SW at 16 - 30 mph.  Surface wind SSE to SSW at 9 - 15 mph.



MONDAY

Mixing height 2000 - 3000 ft during the morning rising to 3500 - 4500 ft during the afternoon.  Transport wind SSW to SW at 15 - 29 mph.  Surface wind SSE to SSW at 9 - 15 mph.



TUESDAY

Mixing height 4500 - 5000 ft during the morning and through the afternoon.  Transport wind SSW to SW at 22 - 38 mph.  Surface wind S to SW at 10 - 18 mph.



3.  BURNING INSTRUCTIONS FOR ZONES 624 AND 625 INCLUDING THE WALKER

    RANGE PORTION OF ZONE 624

This instruction is valid for burning conducted on Saturday and Sunday, February 12 and 13, 2011.

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



For Saturday:



Avoid ignitions within 12 miles to the SSW through SW of SSRAs.  Care needed in selecting units as smoke will likely fumigate along the ground in wind prone areas.  No additional restrictions necessary.



For Sunday:



Avoid ignitions within 15 miles to the S through SW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 30 miles to the S through SW in or near drainages leading to SSRAs.  Recommend against burning units that will smolder significantly overnight.  Complete ignitions by 3 p.m.



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

4.  SPECIAL NOTE:



    The smoke management forecaster is available at (503)

    945-7401.  The smoke management forecaster is available

    to discuss specific burns.  The duty forecaster phone

    number is (503) 945-7401. Please call this number and

    not individual's numbers to discuss daily burning. Please

    avoid calling before 8 a.m. and between 2 to 3 p.m.



    This 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

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://omls.oregon.gov/pipermail/smi_south_central/attachments/20110211/22f84a7f/attachment.html>