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: Wednesday, May 18, 2011       2:40 PM      Pete Parsons



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


THURSDAY

The upper-level trough that has brought unseasonably cool and damp conditions to the region for the past several days will weaken and drift southeastward. It is forecast to stretch from South Dakota to southern California by the afternoon.  The counter-clockwise circulation around it will continue to spin some clouds across the region, but a weak ridge of high pressure, building just offshore, will bring a progressively drier northerly flow.  Drying and warming of the air mass will lift the freezing level to 8-9000 feet.

After a locally frosty morning, abundant sunshine should help maximum temperatures recover to within a few degrees of normal. It will remain cool enough aloft for good daytime mixing with mostly northerly transport winds.

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.  Mostly sunny skies should warm afternoon temperatures back above normal.  Expect good afternoon mixing with light westerly morning transport winds veering to more northwesterly in the afternoon.

On Saturday a weak upper-level trough is forecast to come onshore.  An associated cold front will bring increasing clouds along with a chance of a few showers.  Since the cooler air will be filtering into the region during the day, temperatures may climb to near normal.  Daytime mixing will be good with light westerly transport winds increasing and veering to northwesterly in the afternoon.

Westerly flow aloft is forecast to bring mostly cloudy skies and a chance of showers on Sunday.  Temperatures will cool to about 5 degrees below average.  Daytime mixing should be good with northwesterly transport winds.


2.  DISPERSION



THURSDAY

Mixing height below 1200 ft early rising to 3500 - 4500 ft by late morning.  Afternoon mixing height rises above 5000 ft then lowers to 3000 - 4000 ft during the evening.



Transport wind N to NNE at 12 - 22 mph.



Surface wind NNW to NNE at 9 - 15 mph.



OUTLOOK:



FRIDAY

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 W to NW at 6 - 10 mph during the afternoon.  Surface wind light and variable during the morning becoming W to NW at 6 - 10 mph during the afternoon.



SATURDAY

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



SUNDAY

Mixing height below 1000 ft early rising to 3500 - 4500 ft by late morning rising above 5000 ft during the afternoon.  Transport wind NW to N at 4 - 8 mph.  Surface wind NW to N at 4 - 8 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 Thursday, May 19, 2011.

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



Avoid ignitions within 10 miles to the NNW through NE of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 15 miles to the NNW through ESE 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/20110518/7c27350c/attachment.html>