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, April 29, 2011       2:40 PM      Pete Parsons



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


SATURDAY

An upper-level ridge is forecast to build about 500 miles offshore with a drier and more stable northwesterly flow aloft over Oregon.  The snow level will only lift to about 5000 feet, with the air aloft remaining cold enough for daytime heating to possibly trigger a mountain shower. After a near-record-cold morning, afternoon temperatures will moderate some but remain below normal.  Mixing should be good with northerly transport winds.

OUTLOOK (SUNDAY-TUESDAY)
A progressive upper-level ridge is forecast to move onshore Sunday, with sunny skies expected.  After another near-record-cold morning, high temperatures should rebound close to normal.  The freezing level will jump to around 9000 feet.   Warming aloft will stabilize the air mass, but afternoon mixing should remain good.  Transport winds will slacken and turn mostly southeasterly.

The upper-level ridge will push east of the state Monday with an increasing westerly flow aloft bringing a weak cold front onshore by the afternoon.  Clouds will increase ahead of the cold front, with surface temperatures warming to slightly above normal.  Mixing will be good, with increasing southwesterly transport winds.  In the wake of the dry cold front, the freezing level is only forecast to drop to around 7500 feet late, with the transport winds turning more westerly.

A weak upper-level trough will push east of the state Tuesday, with a return to a dry northwesterly flow aloft.  Skies should be partly cloudy.  The freezing level will rise above 10,000 feet, but cool northwest to north winds will hold surface temperatures near normal.  Afternoon mixing should be good.



2.  DISPERSION



SATURDAY

Mixing height below 1500 ft early rising to 3500 - 4500 ft by late morning.  Afternoon mixing height rises above 5000 ft then lowers to 1500 - 2500 ft during the evening.



Transport wind NNW to NE at 6 - 10 mph during the morning.  Transport wind increases to N to NE at 9 - 15 mph during the afternoon and evening.



Surface wind NNW to NE at 4 - 8 mph during the morning.  Surface wind increases to NNW to NNE at 8 - 12 mph during the afternoon and evening.



OUTLOOK:



SUNDAY

Mixing height below 1000 ft early rising to 3500 - 4500 ft by late morning rising above 5000 ft during the afternoon.  Transport wind light and variable.  Surface wind light and variable.



MONDAY

Mixing height below 1000 ft early rising to 3000 - 4000 ft by late morning rising above 5000 ft during the afternoon.  Transport wind SSW to SW at 12 - 24 mph during the morning becoming WSW to W at 18 - 30 mph during the afternoon.  Surface wind S to SW at 8 - 12 mph during the morning becoming WSW to WNW at 10 - 20 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 NNW to NE at 4 - 8 mph during the morning becoming NW to N at 6 - 10 mph during the afternoon.  Surface wind light and variable during the morning becoming WNW to NNW at 4 - 8 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 Saturday, April 30, 2011.

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



Avoid ignitions within 12 miles to the NNW through NE of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 20 miles to the NNW through E 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/20110429/4a066e9c/attachment.html>