SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Tuesday, May 26, 2015       2:35 PM      Pete Parsons

 

1.  DISCUSSION AND FORECAST FOR NORTHEAST FORECAST AREA ZONES 637-646

 

SHORT-TERM DISCUSSION

A weak upper-level trough, centered over eastern Washington, is producing a relatively dry and cool WNW flow aloft over Oregon.  Skies are partly cloudy skies with a few showers over the NE mountains.  Showers should increase in coverage this afternoon with a few thundershowers, mainly over higher terrain north and east.

The upper-level trough will move over extreme NE Oregon on Wednesday with increasing showers and afternoon thundershowers, mainly east.  Mixing will be excellent.  NW winds may be erratic near showers and thundershowers.

EXTENDED DISCUSSION

The weak upper-level trough will progress into the northern Rockies on Thursday.  Expect mostly partly cloudy skies with good mixing and slackening NW transport winds.  A few showers or afternoon thundershowers may still develop near the Idaho border.

A weak upper-level ridge will move over the region Friday morning and east of the state Friday afternoon.  Increasing WSW flow aloft should force the surface thermal trough into eastern Oregon with temperatures warming to well above average.  After morning inversions, afternoon mixing should be good with light winds.  An isolated thundershower is possible late in the day.

Continued WSW flow aloft will produce partly cloudy skies on Saturday with a chance of afternoon thundershowers, mainly over the mountains.  Transport winds will turn southerly with good daytime mixing.

2.  DISPERSION

 

WEDNESDAY

 

Mixing height below 3000 ft early rising above 5000 ft by late morning.  Mixing height lowers to 3500 - 4500 ft during the evening.

 

Transport wind NW to N at 5 - 9 mph.

 

Surface wind NW to N at 4 - 8 mph.

 

OUTLOOK:

 

THURSDAY

Mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon.  Transport wind light and variable during the morning becoming NW to NNE at 4 - 8 mph during the afternoon.  Surface wind light and variable during the morning becoming NW to NNE at 4 - 8 mph during the afternoon.

 

FRIDAY

Mixing height below 1000 ft early rising to 3000 to 4000 ft by late morning rising above 5000 ft during the afternoon.  Transport wind light and variable.  Surface wind light and variable.

 

SATURDAY

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

 

3.  BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646

    The following considerations should be adhered to in addition to

    the requirements of the Oregon Smoke Management Plan. These

    Instructions are valid for burning done on Wednesday, May 27, 2015.

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Avoid ignitions within 10 miles to the NW through NNE of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 15 miles to the NW through NNE in or near drainages leading to SSRAs.  Verify transport winds away from SSRAs if burning in any other direction. 

 

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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_Information

 

    Please ensure your units have been planned and accomplished by checking:

      http://oregon.gov/ODF/FIRE/SMP/dailysmoke.shtml