SMOKE MANAGEMENT
FORECAST AND INSTRUCTIONS
SALEM FORESTRY
WEATHER CENTER
OREGON DEPARTMENT
OF FORESTRY
ISSUED: Tuesday,
April 21, 2026 2:30 PM Gary Votaw
1. DISCUSSION AND FORECAST FOR NORTHEAST
FORECAST AREA ZONES 637-646
SHORT-TERM
DISCUSSION
A strong upper-level trough passes over the state tonight and Wednesday
with upper flow becoming N by the afternoon.
Conditions will be windy while widespread precipitation typically totals
0.50” to 1.25”. Snow levels persist near
5000 feet as surface temperatures are 15oF below seasonal. Mixing conditions are very good though with strong
W-NW winds.
EXTENDED DISCUSSION
Light showers linger on Thursday as a secondary trough brushes by
the area, snow above 4500-5000 feet. Otherwise,
conditions are partly sunny and chilly. Mixing
becomes excellent with NW winds.
NW flow aloft brings mostly sunny skies but still below normal
temperatures. Burning potential is very
good with light NW transport winds.
There is a chance of light showers on Saturday as
another trough approaches from the north.
Skies will be partly sunny while still cooler than normal. Mixing will be excellent with very light N-NE
winds.
2. DISPERSION
WEDNESDAY
Zone 640, 642,
and 644 West of R35E:
Mixing height
above 5000 ft throughout the day. Mixing
height lowers to 3000 - 4000 ft during the evening.
Transport wind
WSW to WNW at 28 - 48 mph during the morning and afternoon. Transport wind decreases to W to WNW at 22 -
38 mph during the evening.
Surface wind WSW
to WNW at 10 - 18 mph throughout the day.
Zone 637, 643,
645, 646, and 644 East of R34E:
Mixing height 4000
to 5000 ft throughout the day. Mixing
height lowers to 1500 - 2500 ft during the evening.
Transport wind W
to WNW at 33 - 53 mph during the morning.
Transport wind decreases to W to NW at 25 - 45 mph during the afternoon
and decreases to W to NW at 15 - 29 mph during the evening.
Surface wind NW
to NNW at 12 - 24 mph during the morning and afternoon. Surface wind decreases to WSW to WNW at 8 -
14 mph during the evening.
OUTLOOK:
THURSDAY
In the west
mixing height 2000 to 3000 ft during the morning rising above 5000 ft during
the afternoon. In the east mixing height
below 1000 ft early rising to 3900 to 4900 ft by late morning rising above 5000
ft during the afternoon. In the west
transport wind WNW to NW at 16 - 26 mph.
In the east transport wind WNW to NNW at 10 - 18 mph. In the west surface wind light and variable
during the morning becoming WNW to NNW at 6 - 12 mph during the afternoon. In the east surface wind WNW to NW at 10 - 18
mph.
FRIDAY
Mixing height
below 1000 ft early rising to 4300 to 5000 ft by late morning rising above 5000
ft during the afternoon. Transport wind
WNW to NNW at 8 - 14 mph. Surface wind
light and variable during the morning becoming NNW to NNE at 4 - 8 mph during
the afternoon.
SATURDAY
Mixing height
below 1000 ft early rising to 4300 to 5000 ft by late morning rising above 5000
ft during the afternoon. Transport wind
N to NE at 4 - 8 mph. Surface wind N to
NE at 4 - 8 mph.
3. BURNING INSTRUCTIONS FOR NORTHEAST OREGON
ZONES 637-646
- Valid for burning done Wednesday, April
22, 2026.
==================================================================
Zone 640, 642,
and 644 West of R35E:
Follow standard
guidance matrix - see section 5 below - for burning units to the WSW through
WNW of SSRAs. For units that will
smolder significantly through the night avoid burning within at least 10 miles
to the WSW through WNW in or near drainages leading to SSRAs. No additional restrictions necessary.
Zone 637, 643,
645, 646, and 644 East of R34E:
Follow standard
guidance matrix - see section 5 below - for burning units to the W through WNW
of SSRAs. For units that will smolder
significantly through the night avoid burning within at least 15 miles to the W
through NNW in or near drainages leading to SSRAs. Care needed in selecting units as smoke will
likely fumigate along the ground in wind prone areas. 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.