SMOKE MANAGEMENT
FORECAST AND INSTRUCTIONS
SALEM FORESTRY
WEATHER CENTER
OREGON DEPARTMENT
OF FORESTRY
ISSUED: Thursday,
April 9, 2026 2:30 PM Gary Votaw
1. DISCUSSION AND FORECAST FOR THE WESTERN
OREGON AREA FORECAST ZONES 601-623 and 639
SHORT-TERM
DISCUSSION
On Friday an
upper-level trough near the California coast causes S-SE flow and pushes
increasingly moist and unstable air northward.
Showers and possible thunderstorms will begin in the south and spread
northward through West Oregon. Rainfall
totals may reach .25”, to .50” or more in the Cascades, especially in
storms. Temperatures will be near to
above average while snow levels are above 7000 feet. Afternoon mixing will generally be moderate
to good with light SW-W transport winds.
EXTENDED DISCUSSION
The trough weakens while moving inland Saturday, but another upper
low approaches the California coast, reinforcing the moist and unstable SE flow
aloft over West Oregon. Showers increase with still a chance of
thundershowers. Rainfall of .50” to 1.00” in the south will be
common with lesser amounts north as snow levels fall to 5-6000 feet. Look
for good mixing conditions with S transport winds trending SW-W in the
afternoon.
The upper low passes over northern California on Sunday as the
flow aloft becomes weak from N. Showers
continue for West Oregon with another .50” possible in the Cascades and less
elsewhere, snow levels 4000-4500 feet. Mixing
will be good with increasing W-NW winds.
A
weak ridge arrives on Monday with light NW flow. Light showers linger under mostly cloudy skies
while temperatures are below normal.
Burning potential is good with W-NW winds.
2. DISPERSION
FRIDAY
Zone 601, 602,
603 and 612 (North Coast Range):
MORNING
Mixing height below
1000 ft early rising to 1400 - 2400 ft.
Transport wind
light and variable and controlled by local terrain.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing height
1900 - 2900 ft.
Transport wind
increases to SW to W at 4 - 8 mph.
Surface wind
similar to morning.
EVENING
Mixing height
lowers below 1000 ft.
Transport wind SW
to WNW at 6 - 12 mph.
Surface wind
similar to afternoon.
Zone 605-611 and
639 (North Cascades):
MORNING
Mixing height below
1000 ft early rising to 2300 - 3300 ft.
Transport wind S
to SW at 4 - 8 mph.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing height
3200 - 4200 ft.
Transport wind SW
to W at 6 - 12 mph.
Surface wind
similar to morning.
EVENING
Mixing height
1300 - 2300 ft.
Transport wind
similar to afternoon.
Surface wind
similar to afternoon.
Zone 615-620
(South Coast Range):
MORNING
Mixing height below
1000 ft early rising to 1500 - 2500 ft.
Transport wind SW
to WNW at 4 - 8 mph.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing height
rising to 4000 - 5000 ft.
Transport wind
increases to WSW to WNW at 10 - 16 mph.
Surface wind
increases to WSW to WNW at 4 - 8 mph.
EVENING
Mixing height
2500 - 3500 ft.
Transport wind
SSW to WSW at 6 - 10 mph.
Surface wind
becomes light and variable and controlled by local terrain.
Zone 616-623
(South Cascades):
MORNING
Mixing height below
1000 ft early rising to 1500 - 2500 ft.
Transport wind
SSE to SSW at 10 - 18 mph.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing height
rising to 3800 - 4800 ft.
Transport wind
SSW to SW at 10 - 16 mph.
Surface wind
increases to SW to W at 4 - 8 mph.
EVENING
Mixing height
2000 - 3000 ft.
Transport wind
decreases to SW to W at 5 - 9 mph.
Surface wind
becomes light and variable and controlled by local terrain.
OUTLOOK:
SATURDAY
In the north
mixing height below 1000 ft early rising to 2000 to 3000 ft during the morning
rising above 5000 ft during the afternoon.
In the south mixing height 3000 to 4000 ft during the morning rising
above 5000 ft during the afternoon.
Transport wind SSE to SSW at 6 - 12 mph during the morning becoming SW
to W at 5 - 9 mph during the afternoon.
Surface wind light and variable.
SUNDAY
In the north
mixing height below 1000 ft early rising to 2800 to 3800 ft by late morning
rising above 5000 ft during the afternoon.
In the south mixing height below 1000 ft early rising to 4000 to 5000 ft
by late morning rising above 5000 ft during the afternoon. Transport wind SW to WNW at 5 - 9 mph during
the morning becoming WNW to NW at 8 - 14 mph during the afternoon. Surface wind WSW to NW at 4 - 8 mph.
MONDAY
Mixing height 2000
to 3000 ft during the morning rising to 3500 to 4500 ft in the afternoon. Transport wind W to NW at 8 - 12 mph. Surface wind WSW to WNW at 4 - 8 mph.
3. BURNING INSTRUCTIONS FOR ALL ZONES IN THE
WESTERN OREGON AREA
- Valid for burning done Friday, April 10,
2026.
=================================================================
Coast Range
Zone 601
Units should be
500 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs. North of Tillamook, use standard guidance
matrix. (See section 5 below.)
Zone 602 and 603
No burning
allowed. North of T3N in Zone 602, use
standard guidance matrix. (See section 5 below.) Limit burning in or near corridors. Units may be 500 tons or less, spaced 12
miles apart, south of the Siuslaw River in Zone 603.
Zone 615
Units should be
1500 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs.
Zone 616 west of
R8W
Units should be
1200 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs. Higher tonnage is possible south of
T29S. Call the forecaster.
Zone 616 east of
R9W
Units should be
750 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs. Higher tonnage is possible south of
T29S. Call the forecaster.
Zone 618 and 619
Use standard
guidance matrix. (See section 5 below.)
Zone 620
Units should be
600 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs.
Cascades
All zones except
zone 611
Use standard
guidance matrix - see section 5 below.
Ensure adequate distance from downwind SSRAs for smoke to
dissipate. From T18S through T22S in
Zone 608 units should be 900 tons or less, spaced 8 miles apart. Avoid ignitions north of T24S in Zone 616.
Zone 611
Units should be
900 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.
Siskiyous
Units should be
1200 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs.
==============================================================
4. SPECIAL NOTES:
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
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 they will return your
call as soon as possible.
Avoid calling between 1:30 to 2:45 p.m.
The forecast is available on the Internet
at:
http://www.odf.state.or.us/DIVISIONS/protection/fire_protection/
Daily/smi.htm
Please ensure your units have been planned
and accomplished by
checking:
http://www.oregon.gov/ODF/Fire/Pages/Burn.aspx
A map of planned and/or accomplished burns
is located at:
http://geo.maps.arcgis.com/apps/webappviewer/index.html
?id=a7e321dc8fc444b7a33fbc67bc673a3b
The forecast/instruction telephone
recording is: (503) 945-7400.
To subscribe to or unsubscribe from the
email list for this
product, please go to the link:
http://weather.smkmgt.com/mailman/listinfo/
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.
Example: 300 tons allowed if burned 5 miles
from a downwind SSRA.
* 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.