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: Saturday, May 21, 2011       2:40 PM      Pete Parsons



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


SUNDAY

An upper-level trough is forecast to extend from the Gulf of Alaska southeastward to over the Pacific Northwest. The second in a series of embedded weather disturbances will rotate onshore during the day.  Southwesterly flow aloft will keep skies partly to mostly cloudy with a chance of light showers.

High temperatures will likely be about 5 degrees below normal, with cooling aloft maintaining good daytime mixing.  Light morning winds will increase from the west-northwest in the afternoon.

OUTLOOK (MONDAY-WEDNESDAY)

A moderately strong upper-level trough will rotate another embedded weather disturbance onshore Monday.  This system looks to be a little stronger than the previous two with enough energy directed at southern Oregon to maintain a chance of mainly afternoon and evening showers.  The snow level will drop to about 6000 feet with maximum temperatures running 5-10 degrees below average.  Smoke dispersal conditions should be good with increasing northwesterly transport winds.

The upper-level trough is forecast to weaken by Tuesday, as it moves off to the east.  A weak and transitory upper-level ridge will slowly clear skies with maximum temperatures recovering to within 5 degrees of normal. Daytime mixing will remain good, with transport winds slackening and turning more southwesterly.

An impressive upper-level trough is forecast to approach the coastline on Wednesday, as a strengthening southwesterly jet stream directs an active cold front across the state.  Skies will turn cloudy with showers developing in the afternoon.  Brisk south-southwesterly winds will veer to more westerly in the afternoon with good daytime mixing.



2.  DISPERSION



SUNDAY

Mixing height below 1000 ft early rising to 3000 - 4000 ft by late morning.  Afternoon mixing height rises above 5000 ft then lowers to 2000 - 3000 ft during the evening.



Transport wind light and variable and controlled by local terrain during the morning.  Transport wind increases to W to NW at 9 - 15 mph during the afternoon and evening.



Surface wind light and variable and controlled by local terrain during the morning.  Surface wind increases to WNW to NW at 9 - 15 mph during the afternoon and evening.



OUTLOOK:



MONDAY

Mixing height below 1000 ft early rising to 3500 - 4500 ft by late morning rising above 5000 ft during the afternoon.  Transport wind WNW to NNW at 6 - 10 mph.  Surface wind WNW to NNW at 4 - 8 mph during the morning becoming WNW to NW at 9 - 15 mph during the afternoon.



TUESDAY

Mixing height below 1000 ft early rising to 3000 - 4000 ft by late morning rising above 5000 ft during the afternoon.  Transport wind light and variable during the morning becoming SSW to WSW at 6 - 10 mph during the afternoon.  Surface wind light and variable during the morning becoming SSW to WSW at 4 - 8 mph during the afternoon.



WEDNESDAY

Mixing height below 1000 ft early rising to 3500 - 4500 ft by late morning rising above 5000 ft during the afternoon.  Transport wind S to SW at 15 - 25 mph during the morning becoming SW to WSW at 18 - 32 mph during the afternoon.  Surface wind SSE to SSW at 9 - 15 mph during the morning becoming SW to W at 10 - 20 mph during the afternoon.



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

    RANGE PORTION OF ZONE 624

This instruction is valid for burning conducted on Sunday, May 22, 2011.

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



Avoid ignitions within 12 miles to the WSW through NNW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 20 miles to the WSW through N in or near drainages leading to SSRAs.



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

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/20110521/79783799/attachment.html>