SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Friday, November 21, 2014       2:35 PM      Tom Jenkins

 

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

 

SHORT-TERM DISCUSSION

The atmosphere is unstable, with an upper level trough coming onshore overnight Friday. The surface frontal system ahead of this feature will continue to provide onshore flow and good mixing early Saturday morning. The atmosphere will become less stable mid-day, as the upper level trough passes into the Cascades and rain becomes more showery. Colder air behind the frontal system will drop the freezing level to 4,000ft after sunset.

EXTENDED DISCUSSION

The atmosphere will begin to stabilize on Sunday morning, as an upper level ridge starts to build offshore. Spotty showers will develop in western zones as a weak mid-level trough skims across northern Oregon Sunday afternoon, enhancing mixing conditions as it approaches. The atmosphere will continue to stabilize overnight as the upper level ridge builds and shifts into western Oregon. A surface ridge will begin to form Monday, turning winds light and influenced primarily by terrain. Mixing will be suppressed as a result. Stable conditions will persist overnight into Tuesday, as the upper level ridge moves into the Cascades and the surface ridge builds. Winds will shift to favor a S direction, as the surface ridge slides to the east. Mixing will begin poor and see limited improvement as a result.

 

2.  DISPERSION

 

SATURDAY

 

Zone 640, 642, and 644 West of R35E:

Mixing height above 5000 ft throughout the day.  Mixing height lowers to 1500 - 2500 ft during the evening.

 

Transport wind WSW to WNW at 15 - 29 mph during the morning and afternoon.  Transport wind decreases to W to NW at 10 - 20 mph during the evening.

 

Surface wind SW to WSW at 8 - 12 mph during the morning and afternoon.  Surface wind decreases to WSW to WNW at 6 - 12 mph during the evening.

 

Zone 637, 643, 645, 646, and 644 East of R34E:

Mixing height 4000 - 5000 ft during the morning.  Mixing height rises to above 5000 ft during the afternoon then lowers to 1500 - 2500 ft during the evening.

 

Transport wind W to NW at 20 - 34 mph during the morning.  Transport wind decreases to W to NW at 10 - 20 mph during the afternoon then increases to NW to NNW at 18 - 32 mph during the evening.

 

Surface wind WNW to NW at 10 - 20 mph during the morning.  Surface wind decreases to W to NW at 6 - 12 mph during the afternoon then increases to WNW to NW at 10 - 22 mph during the evening.

 

OUTLOOK:

 

SUNDAY

Mixing height 1600 to 2600 ft during the morning rising to 3200 to 4200 ft during the afternoon.  Transport wind WSW to WNW at 8 - 14 mph.  Surface wind SSE to SW at 5 - 7 mph.

 

MONDAY

Mixing height 1000 to 2000 ft during the morning rising to 2500 to 3500 ft during the afternoon.  Transport wind SSE to SSW at 4 - 8 mph.  Surface wind ENE to ESE at 5 - 9 mph during the morning becoming ESE to SSE at 5 - 9 mph during the afternoon.

 

TUESDAY

Mixing height 1200 to 2200 ft during the morning rising to 2500 to 3500 ft during the afternoon.  Transport wind SW to W at 4 - 8 mph.  Surface wind SSE to SSW at 5 - 9 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 conducted on Saturday, November 22, 2014.

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Zone 640, 642, and 644 West of R35E:

Avoid ignitions within 12 miles to the WSW through NW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 20 miles to the WSW through NW in or near drainages leading to SSRAs.  Complete ignitions by 3 p.m. 

 

Zone 637, 643, 645, 646, and 644 East of R34E:

Avoid ignitions within 12 miles to the W through NNW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 20 miles to the WSW through NNW in or near drainages leading to SSRAs.  Care needed in selecting units as smoke will likely fumigate along the ground in wind prone areas.  Complete ignitions by 3 p.m. 

 

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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