SMI Northeast (Smoke Management Instructions) Northeast Oregon 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       2:35 PM      Pete Parsons



1.  DISCUSSION AND FORECAST FOR NORTHEAST FORECAST AREA ZONES 630-638


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, however, will continue to spin some clouds across northeastern Oregon, with the possibility of a stray shower, mainly east and over higher terrain.  Meanwhile, a weak ridge of high pressure will build just offshore, with a drier northerly flow progressing from west-to-east across the region.  Continued drying and warming of the air mass will lift the freezing level to 7-8000 feet.

After a chilly early morning, afternoon clearing should help warm maximum temperatures to near average. 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.  Skies should become partly cloudy with just a risk of a mountain shower east.   Maximum temperatures will be near to slightly above average, which will make for good afternoon mixing.  Transport winds will be north-northwesterly.

On Saturday a weak upper-level trough is forecast to come onshore, along with a surface cold front.  The weakening cold front is forecast to bring increasing clouds and a chance of showers in the afternoon, with west to northwesterly transport winds.  Since the cooler air will not arrive until late in the day, maximum temperatures should climb to slightly above normal.  Daytime mixing should be fair to good.

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 1500 ft early rising to 3000 - 4000 ft by late morning.  Afternoon mixing height rises above 5000 ft then lowers to 3200 - 4200 ft during the evening.



Transport wind N to NNE at 11 - 21 mph.



Surface wind NNW to NNE at 9 - 15 mph during the morning and afternoon.  Surface wind decreases to NNW to NNE at 6 - 11 mph during the evening.



OUTLOOK:



FRIDAY

Mixing height 2000 to 3000 ft during the morning rising above 5000 ft during the afternoon.  Transport wind NW to NNE at 6 - 10 mph.  Surface wind light and variable during the morning becoming NW to N at 5 - 9 mph during the afternoon.



SATURDAY

Mixing height below 1000 ft early rising to 3500 to 4500 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 WNW to NNW at 5 - 9 mph during the afternoon.



SUNDAY

Mixing height below 1000 ft early rising to 3000 to 4000 ft by late morning rising above 5000 ft during the afternoon.  Transport wind W to NW at 4 - 8 mph during the morning becoming NW to NNW at 8 - 12 mph during the afternoon.  Surface wind WNW to NNW at 4 - 8 mph.



3.  BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 630-638

    The following considerations should be adhered to in addition to

    the requirements of the Oregon Smoke Management Plan. These

    Instructions are valid for burning conducted on Thursday, May 19, 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 NW through NE in or near drainages leading to SSRAs.



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

4.  SPECIAL NOTE:



    The smoke management forecaster is available at (503)-

    945-7401. Please call this number and not individual's

    numbers to discuss daily burning.  For large burns (over

    2000 tons) or burns extending over a considerable period,

    please request a special forecast.  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

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