SMOKE MANAGEMENT
FORECAST AND INSTRUCTIONS
SALEM FORESTRY
WEATHER CENTER
OREGON DEPARTMENT
OF FORESTRY
ISSUED: Monday,
December 9, 2013 2:30 PM Pete Parsons
**************** Air Stagnation Advisory Information
***************
The National Weather Service has issued Air
Stagnation Advisories for the interior of SW Oregon and for south-central
Oregon; including Roseburg, Grants Pass, Medford, Ashland, Crescent, Silver
Lake, Klamath Falls, and Lakeview through 4 a.m. Thursday, December 12th.
**Please use extra precautions and limit
forestland burning to units that will not worsen air quality within nearby
SSRAs. **
**Note:
Special Protection Zone Restrictions may apply**
**Current Air Stagnation Advisories link: http://www.wrh.noaa.gov/ **
*********************************************************************
1. DISCUSSION AND FORECAST FOR THE WESTERN OREGON AREA FORECAST ZONES 601-623
A record-setting
cold air mass remains entrenched across the Pacific Northwest. This morning’s temperatures were not quite as
cold as they were on Sunday but still near daily records. Eugene bottomed out at 2 degrees below zero
(after hitting 10 degrees below zero Sunday morning); just missing their daily
record for December 9th of 5 degrees below zero; set in 1972. Eugene records go back to 1892.
An upper-level ridge
of high pressure is slowly trying to push over Oregon; warming the air aloft
and creating low-level inversions.
However, a weak upper-level disturbance is backing the flow aloft to the
NW; forcing a shallow layer of moist marine air over the top of the existing
Arctic dome across western Washington and NW Oregon.
Low clouds are
advancing across the northern zones this afternoon with increasing areas of
very light snow. Widespread valley fog
gave way to mostly sunny skies over the southern zones this afternoon. Areas of very light snow are possible tonight
over the extreme northern zones, with freezing valley fog reforming across the
central and southern zones. Temperatures
will continue to slowly moderate.
Very little change
in the weather pattern is forecast for Tuesday.
The stable air mass will continue to slowly moderate under a NW flow
aloft. Surface winds should remain
weakly offshore. Northern zones will
maintain mostly cloudy skies with a threat of light precipitation at times. Coastal regions should see a change-over to
rain or drizzle, but precipitation across inland areas will remain as snow,
sleet, and/or freezing rain. Southern zones should remain dry with continued stagnant
conditions.
EXTENDED DISCUSSION
The upper-level
ridge is forecast to strengthen over Oregon on Wednesday; shutting off the
precipitation threat and continuing the slow moderation process. Additional warming aloft will strengthen
low-level inversions and maintain poor ventilation conditions. Light transport winds should turn mostly
southeasterly.
More significant
changes will begin on Thursday, as the upper-level ridge weakens and shifts
east of the region; allowing a weak Pacific storm to move onshore. Increasing
south to SE winds should finally warm inland valley temperatures above
freezing, except for areas in and near the Columbia Gorge. Ventilation conditions should begin to
improve for most areas Thursday afternoon, as light rain spreads inland across
western Oregon. However, areas of snow,
sleet and freezing rain are possible in and near the Columbia Gorge. By Thursday night, even the Gorge and central
Oregon may see enough warming for a general change-over to rain below about
5000 feet.
An upper-level ridge
will bring a drying and stabilizing NW flow aloft on Friday. With a more moderate Pacific air mass over
the region, mixing will improve, but winds will be light.
2. DISPERSION
TUESDAY
Zone 601, 602,
603 and 612 (North Coast Range):
MORNING
Mixing
height below 1000 ft.
Transport wind
light and variable and controlled by local terrain.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing
height 1000 - 2000 ft.
Transport wind
similar to morning.
Surface
wind similar to morning.
EVENING
Mixing height
lowers below 1000 ft.
Transport wind
similar to afternoon.
Surface
wind similar to afternoon.
Zone 605-611
(North Cascades):
MORNING
Mixing
height below 1000 ft.
Transport wind
light and variable and controlled by local terrain.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing
height 1000 - 2000 ft.
Transport wind
similar to morning.
Surface
wind similar to morning.
EVENING
Mixing height
lowers below 1000 ft.
Transport wind
similar to afternoon.
Surface
wind similar to afternoon.
Zone 615-620
(South Coast Range):
MORNING
Mixing
height below 1000 ft.
Transport wind NE
to ESE at 4 - 8 mph.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing
height 1000 - 2000 ft.
Transport wind
similar to morning.
Surface
wind similar to morning.
EVENING
Mixing height
lowers below 1000 ft.
Transport wind
similar to afternoon.
Surface
wind similar to afternoon.
Zone 616-623
(South Cascades):
MORNING
Mixing
height below 1000 ft.
Transport wind
light and variable and controlled by local terrain.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing height
remains below 1000 ft.
Transport wind
similar to morning.
Surface
wind similar to morning.
EVENING
Mixing height
remains below 1000 ft.
Transport wind
similar to afternoon.
Surface
wind similar to afternoon.
OUTLOOK:
WEDNESDAY
Mixing
height below 1000 ft throughout the day. Transport wind E to SE
at 4 - 8 mph. Surface
wind light and variable.
THURSDAY
Mixing
height below 1000 ft early rising to 1000 to 1600 ft by late morning rising to
1500 to 2500 ft during the afternoon. Transport wind E to SE
at 4 - 8 mph during the morning becoming SSE to SSW at 8 - 12 mph during the
afternoon. Surface
wind SE to SSW at 4 - 8 mph.
FRIDAY
Mixing
height 1000 to 1600 ft during the morning rising to 2900 to 3900 ft during the
afternoon. Transport wind light and variable. Surface wind light and
variable.
3. BURNING INSTRUCTIONS FOR ALL ZONES IN THE
WESTERN OREGON AREA
Instructions are
valid for burning done on Tuesday,
December 10, 2013.
=================================================================
Coast Range
***Complete
ignitions by 2:30 p.m. in all zones.***
Zone 601 and 612
Units should be
750 tons or less, spaced 15 miles apart, and 15 miles from downwind SSRAs.
Zone 602 and 603
No burning
allowed.
Zone 615, 616,
618, 619, and 620
Use standard
guidance matrix. (See section 5 below.)
Avoid burning directly upwind of the North Bend/Coos Bay SSRA.
Cascades
***Complete ignitions
by 2:30 p.m. in all zones.***
Zone 605, 606,
620, and 622
No burning
allowed.
Zone 607, 608,
and 616
Units should be
500 tons or less, spaced 15 miles apart, and 15 miles from downwind SSRAs.
Zone 609, 610,
and 611
Units should be
1000 tons or less, spaced 15 miles apart, and 15 miles from downwind SSRAs.
Zone 617 and 623
Use standard
guidance matrix. (See section 5 below.)
South of T30S in Zone 617 units should be 500 tons or less, spaced 15
miles apart.
Siskiyous
***Complete ignitions
by 2:30 p.m.***
Use standard
guidance matrix. (See section 5 below.)
==============================================================
4. SPECIAL NOTE:
Call the smoke management duty forecaster
at (503) 945-7401 to
discuss
burning. Please do not call individual's
numbers to
discuss daily
burning. If the forecaster is not
available,
leave a message
and he will return your call as soon as possible.
Avoid calling between 2 to 2:30 p.m.
The 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
The forecast/instruction telephone
recording is: (503) 945-7400.
Submit feedback at:
http://weather.smkmgt.com/feedback.
5. STANDARD GUIDANCE MATRIX:
* Greater than 5000 ft mixing height: No burning within 5 miles of
downwind
SSRA. Limit to 100 tons per mile from
downwind SSRA.
Example:
500 tons allowed if burned 5 miles from downwind SSRA.
* 3000 - 5000 ft mixing height: No burning within 10 miles of
downwind
SSRA. Limit to 75 tons per mile from
downwind SSRA.
Example:
750 tons allowed if burned 10 miles from downwind SSRA.
* Less than 3000 ft mixing height: No burning within 15 miles of
downwind
SSRA. Limit to 50 tons per mile from
downwind SSRA.
Example:
750 tons allowed if burned 15 miles from downwind SSRA.
* All exceptions must be coordinated with the
duty forecaster
prior to ignition.