SMI South Central (Smoke Management Instructions) South Central Smoke Management Instructions
ODF Smoke Management Instructions
smi_south_central at listsmart.osl.state.or.us
Thu Nov 4 14:31:52 PDT 2010
SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS
SALEM FORESTRY WEATHER CENTER
OREGON DEPARTMENT OF FORESTRY
ISSUED: Thursday, November 4, 2010 2:40 PM Pete Parsons
1. DISCUSSION AND FORECAST FOR SOUTH CENTRAL OREGON ZONES 624 AND 625
The massive upper-level ridge of high pressure that has been bringing unseasonably warm temperatures and stagnant ventilation conditions will weaken and shift slightly eastward. The ridge axis is forecast to stretch from Utah through eastern Montana with a slowly strengthening southwesterly flow aloft over Oregon.
The first in a series of progressively stronger weather systems will fall apart along the coastline, with just a few clouds will drifting over the region. Warm air aloft will continue to suppress mixing heights. However, increasing southerly surface and transport winds may locally mix warmer air aloft to the surface, resulting in near-record warm surface temperatures and improved smoke dispersal conditions.
The second in a series of weather systems will approach the coastline on Saturday, but it appears as if any significant rainfall will stay offshore until evening. Clouds will be on the increase over south-central Oregon with a slight chance of light showers rotating over the region from California. South to southwesterly winds will keep surface temperatures well above normal, and cooling aloft will raise afternoon mixing heights, making for good smoke dispersal conditions.
A cold front will likely spread rain across western Oregon by Saturday night and into south-central Oregon Sunday morning. Rain will turn to showers later Sunday afternoon. Rainfall amounts should range from one-tenth to one-quarter of an inch. Surface temperatures will cool to near normal. Cooler air aloft will drop the snow level to around 5000 feet, by evening, with continued good afternoon smoke dispersal conditions. Showers will taper off Sunday night.
A flat and transitory upper-level ridge will being some drying on Monday and may suppress afternoon mixing heights slightly. Surface temperatures will cool to slightly below normal with a continued threat of showers, mainly east in the morning. Transport winds will remain onshore with fair to good smoke dispersal conditions.
Mixing height below 800 ft early rising to 2000 - 3000 ft by late morning. Afternoon mixing height rises to 3000 - 4000 ft then lowers to 1000 - 2000 ft during the evening.
Transport wind SSW to SW at 12 - 22 mph during the morning and afternoon. Transport wind decreases to SSE to SSW at 8 - 12 mph during the evening.
Surface wind SSE to SSW at 6 - 10 mph.
Mixing height below 1000 ft early rising to 2000 - 3000 ft by late morning rising to 4000 - 5000 ft during the afternoon. Transport wind S to SW at 10 - 20 mph during the morning becoming SSW to SW at 15 - 25 mph during the afternoon. Surface wind SSE to SSW at 6 - 10 mph.
Mixing height 2000 - 3000 ft during the morning rising to 4500 - 5000 ft during the afternoon. Transport wind SSW to SW at 18 - 32 mph during the morning becoming WSW to WNW at 10 - 20 mph during the afternoon. Surface wind S to SW at 8 - 12 mph during the morning becoming WSW to WNW at 4 - 8 mph during the afternoon.
Mixing height below 1000 ft early rising to 2500 - 3500 ft by late morning rising to 3500 - 4500 ft during the afternoon. Transport wind W to NW at 8 - 12 mph. Surface wind WSW to NW at 4 - 8 mph.
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, November 5, 2010.
Avoid ignitions within 15 miles to the S through WSW of SSRAs. For units that will smolder significantly through the night avoid burning within at least 30 miles to the SSE through WSW in or near drainages leading to SSRAs. Recommend against burning units that will smolder significantly overnight. Complete ignitions by 3:30 p.m.
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:
Please ensure your units have been planned and accomplished by checking:
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