SMOKE MANAGEMENT
FORECAST AND INSTRUCTIONS
SALEM FORESTRY
WEATHER CENTER
OREGON DEPARTMENT
OF FORESTRY
ISSUED:
Wednesday, December 3, 2025 2:30 PM Pete Parsons
1. DISCUSSION AND
FORECAST FOR NORTHEAST FORECAST AREA ZONES 637-646
SHORT-TERM DISCUSSION
High pressure built back over the state today for a return
to dry conditions, poor mixing, and light winds.
A warm front brings areas of rain and snow on Thursday with
light S-SW winds and near-average temperatures.
Mild air aloft will maintain poor mixing.
EXTENDED DISCUSSION
The upper-level ridge flattens on Friday, allowing a
stronger weather system to spread more rain and snow across the region. Snow levels will locally be near the higher
valley floors. Precipitation over .25”
is likely. Mixing will improve with
increasing west winds.
A strong NW flow aloft continues Saturday and Sunday along
with mostly cloudy skies and areas of rain and snow. Snow levels will vary from 4-6000 feet with better
mixing on Saturday than on Sunday. Winds will be mostly westerly on Saturday
and SW on Sunday.
2. DISPERSION
THURSDAY
Zone 640, 642,
and 644 West of R35E:
Mixing height
below 1000 ft during the morning.
Afternoon mixing height rising to 1700 - 2700 ft then remains near 1700
- 2700 ft during the evening.
Transport wind SW
to W at 4 - 8 mph during the morning.
Transport wind increases to WSW to WNW at 8 - 12 mph during the
afternoon and evening.
Surface wind
light and variable and controlled by local terrain during the morning. Surface wind increases to SW to W at 4 - 8
mph during the afternoon and evening.
Zone 637, 643,
645, 646, and 644 East of R34E:
Mixing height
below 1000 ft during the morning.
Afternoon mixing height rising to 1300 - 2300 ft then remains near 1300
- 2300 ft during the evening.
Transport wind S
to SW at 4 - 8 mph throughout the day.
Surface wind
light and variable and controlled by local terrain during the morning. Surface wind increases to SSE to SSW at 4 - 8
mph during the afternoon then shifts to SW to W at 4 - 8 mph during the
evening.
OUTLOOK:
FRIDAY
Mixing height
1300 to 2300 ft during the morning rising to 3500 to 4500 ft during the
afternoon. Transport wind WSW to WNW at
12 - 22 mph during the morning becoming WSW to WNW at 22 - 38 mph during the
afternoon. Surface wind WSW to WNW at 7
- 13 mph during the morning becoming WSW to WNW at 10 - 20 mph during the
afternoon.
SATURDAY
Mixing height
2000 to 3000 ft during the morning rising to 4000 to 5000 ft during the
afternoon. Transport wind WSW to WNW at
15 - 25 mph. Surface wind WSW to WNW at
9 - 15 mph.
SUNDAY
Mixing height
1400 to 2400 ft during the morning rising to 3500 to 4500 ft during the
afternoon. Transport wind S to SSW at 12
- 24 mph. Surface wind SE to SSW at 8 -
12 mph.
3. BURNING
INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646
- Valid for burning done Thursday, December
4, 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 to the SSW
through NW of SSRAs. For units that will
smolder significantly through the night avoid burning within at least 30 miles
to the SSW through NW in or near drainages leading to SSRAs. Verify transport winds away from SSRAs if
burning in any other direction. 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 SSE through WNW of SSRAs. For units
that will smolder significantly through the night avoid burning within at least
30 miles to the SSE through WNW in or near drainages leading to 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.