SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Thursday, October 23, 2014       2:40 PM      Tom Jenkins

 

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

 

SHORT-TERM DISCUSSION

An upper level trough offshore of California will deepen significantly, causing upper level ridging to build over southern Oregon Friday. The atmosphere will stabilize with light winds shifting offshore as a weak surface ridge develops. A warm front will sweep north of the region mid-day, bringing rain. Precipitation will taper off by sunset and winds will shift to light onshore flow.

EXTENDED DISCUSSION

The weather pattern will remain active into the early weekend, as the upper level trough moves onshore. The cold front will bring scattered showers and improved mixing conditions to the western zones, but will get slowed down by the Cascades. The surface frontal boundary will rapidly dissipate and showers will taper off Saturday night.

Another upper level trough will begin to deepen offshore, causing upper level ridging to develop over Oregon Sunday. This will begin a period of stabilization. Warm air aloft will move over southern Oregon, capping mixing and helping a weak surface ridge to form. Winds will become light and shift to offshore flow as the upper level trough offshore continues to deepen Sunday night. As this trough begins to form a surface frontal system, winds will transition back to onshore flow Monday. Mixing heights, however, will still be restricted as warmer air remains in place aloft.

 

2.  DISPERSION

 

FRIDAY

 

Mixing height 1500 - 2500 ft during the morning.  Afternoon mixing height rises to 2000 - 3000 ft then lowers to 1500 - 2500 ft during the evening.

 

Transport wind SSE to S at 15 - 25 mph during the morning.  Transport wind increases to S to SSW at 18 - 32 mph during the afternoon and evening.

 

Surface wind SE to S at 8 - 12 mph during the morning.  Surface wind increases to SSE to SSW at 10 - 20 mph during the afternoon and evening.

 

OUTLOOK:

 

SATURDAY

Mixing height below 1000 ft early rising to 2000 - 3000 ft by late morning and through the afternoon.  Transport wind S to SSW at 28 - 48 mph.  Surface wind S to SSW at 16 - 30 mph.

 

SUNDAY

Mixing height below 1000 ft early rising to 3600 - 4600 ft by late morning and through the afternoon.  Transport wind WSW to WNW at 10 - 20 mph.  Surface wind SW to W at 8 - 12 mph.

 

MONDAY

Mixing height below 1000 ft early rising to 1500 - 2500 ft by late morning rising to 3000 - 4000 ft during the afternoon.  Transport wind SE to S at 4 - 8 mph.  Surface wind SSE to SSW at 4 - 8 mph during the morning becoming light and variable 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 Friday, October 24, 2014.

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Avoid ignitions within 20 miles to the SSE through SSW of SSRAs. 

 

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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_Information

 

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

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