SMOKE MANAGEMENT
FORECAST AND INSTRUCTIONS
SALEM FORESTRY
WEATHER CENTER
OREGON DEPARTMENT
OF FORESTRY
ISSUED: Tuesday,
December 2, 2025 2:30 PM Gary Votaw
1. DISCUSSION AND FORECAST FOR NORTHEAST
FORECAST AREA ZONES 637-646
SHORT-TERM
DISCUSSION
Flow aloft is N on Wednesday in response to a strong and very
large ridge centered offshore. The ridge
is responsible for poor burning potential in NE Oregon with light and variable
winds. Partly sunny skies will allow for average temperatures
through the day.
EXTENDED
DISCUSSION
The ridge
and N flow aloft persists on Thursday, but a warm front will be near the coast. Skies will be mostly cloudy and some of the
moisture associated with the front may reach NE Oregon for very light rain, or
snow above 4500-5000 feet. However, burning
conditions remain poor while SW transport winds in the morning trend W by
afternoon.
The ridge weakens
by Friday, allowing moist air to increasingly flow into the Pacific NW. Expect periods of rain and snow. Snow levels will rise to 6500-7500 feet while
precipitation over .25” is likely in mountains. Strong west winds are
likely but mixing will otherwise be much improved.
Lingering light rain and mountain snow remains likely
at times through the weekend, skies remaining mostly cloudy. NW flow aloft continues while still another
weak trough arrives late on Sunday. Mixing
potential is generally very good on both afternoons with W transport winds.
2. DISPERSION
WEDNESDAY
Zone 640, 642,
and 644 West of R35E:
Mixing height
below 1000 ft during the morning.
Afternoon mixing height rising to 1000 - 1900 ft then lowering below
1000 ft during the evening.
Transport wind light
and variable and controlled by local terrain during the morning and afternoon
then increases to SW to WNW at 5 - 9 mph during the evening.
Surface wind
light and variable and controlled by local terrain.
Zone 637, 643,
645, 646, and 644 East of R34E:
Mixing height
below 1000 ft during the morning.
Afternoon mixing height rising to 1000 - 1900 ft then lowering below
1000 ft during the evening.
Transport wind light
and variable and controlled by local terrain during the morning and afternoon
then increases to SW to W at 6 - 12 mph during the evening.
Surface wind
light and variable and controlled by local terrain.
OUTLOOK:
THURSDAY
Mixing height
below 1000 ft during the morning rising to 1100 to 2100 ft during the
afternoon. Transport wind SSW to WSW at
5 - 9 mph during the morning becoming WSW to WNW at 10 - 16 mph during the
afternoon. Surface wind light and
variable during the morning becoming SW to W at 4 - 8 mph during the afternoon.
FRIDAY
Mixing height
below 1000 ft early rising to 3500 to 4500 ft by late morning rising to 4400 to
5000 ft during the afternoon. Transport
wind WSW to WNW at 28 - 48 mph. Surface
wind W to WNW at 13 - 25 mph.
SATURDAY
Mixing height
below 1000 ft early rising to 4000 to 5000 ft by late morning and through the
afternoon. Transport wind WSW to WNW at
15 - 29 mph during the morning becoming WSW to WNW at 10 - 18 mph during the
afternoon. Surface wind SSW to WSW at 6
- 12 mph.
3. BURNING INSTRUCTIONS FOR NORTHEAST OREGON
ZONES 637-646
- Valid for burning done Wednesday,
December 3, 2025.
==================================================================
Zone 640, 642,
and 644 West of R35E:
Delay
ignitions until 10 a.m. Follow
standard guidance matrix - see section 5 below - for burning units in all
directions of SSRAs. For units that will
smolder significantly through the night avoid burning within at least 30 miles
in all directions of SSRAs. Complete ignitions by 2:30 p.m. No additional
restrictions necessary.
Zone 637, 643,
645, 646, and 644 East of R34E:
Delay
ignitions until 10 a.m. Follow
standard guidance matrix - see section 5 below - for burning units to the SW
through N of SSRAs. For units that will
smolder significantly through the night avoid burning within at least 30 miles
in all directions of SSRAs. Verify
transport winds away from SSRAs if burning in any other direction. Complete ignitions by 2:30 p.m. No additional restrictions necessary.
=========================================================
4. SPECIAL NOTE:
The ODF forecast smoke zones differ from
the NWS fire zones and
are available at:
https://www.oregon.gov/odf/fire/documents/smoke-forecast-zone-map.pdf
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
between 1:30 to 2:45 p.m.
http://www.odf.state.or.us/DIVISIONS/protection/fire_protection/
Daily/neo.htm
To subscribe to or unsubscribe from the
email list for this
product, please go to the link:
http://weather.smkmgt.com/mailman/listinfo/
Please ensure your units have been planned
and accomplished by
checking:
http://oregon.gov/ODF/FIRE/SMP/dailysmoke.shtml
A map of planned and/or accomplished burns
is located at:
http://geo.maps.arcgis.com/apps/webappviewer/index.html
?id=a7e321dc8fc444b7a33fbc67bc673a3b
5. STANDARD GUIDANCE MATRIX:
* Greater than 5000 ft mixing height: Limit
to 150 tons per mile
from downwind SSRAs.
Example: 75 tons allowed if burned a half
mile from a downwind
SSRA.
* 3000 - 5000 ft mixing height: Limit to 50
tons per mile if
burning within 5 miles of downwind SSRAs.
Limit to 100 tons
per mile if burning 5 miles or beyond
downwind SSRAs.
Example #1: 200 tons allowed if burned 4
miles from a downwind
SSRA.
Example #2: 500 tons allowed if burned 5
miles from a downwind
SSRA.
* Less than 3000 ft mixing height: No burning
within 5 miles of
downwind SSRAs. Limit to 60 tons per mile
from downwind SSRAs.
* Ensure adequate spacing between units when
burning near downwind
SSRAs.
* Use of polyethylene (PE) sheeting on
greater than 75 percent of
piles in a unit with 60 percent coverage
per pile will allow a
50 percent increase in tonnage over the
existing instruction tonnage
for that zone.
* All exceptions must be coordinated with the
duty forecaster
prior to ignition.
6. BURN MONITORING:
Burns over 2000 tons must be monitored (OAR
629-048-0230(3) -
7/1/14). Monitoring of all burns is highly
recommended for both
smoke management purposes and wildfire
potential.