SMOKE MANAGEMENT
FORECAST AND INSTRUCTIONS
SALEM FORESTRY
WEATHER CENTER
OREGON DEPARTMENT
OF FORESTRY
ISSUED: Thursday,
May 21, 2026
2:30 PM Pete Parsons
1. DISCUSSION AND
FORECAST FOR THE WESTERN OREGON AREA FORECAST ZONES 601-623 and 639
SHORT-TERM DISCUSSION
A dry and stable NW flow aloft will bring sunny skies again
on Friday with afternoon temperatures about 15°F above average. Mixing will be limited in coastal regions,
but strong surface heating will provide good afternoon mixing east of the coast
range. A weak surface thermal trough shifts from western to central Oregon in the
afternoon, turning winds mostly NW.
EXTENDED DISCUSSION
The upper-level ridge weakens on Saturday with the flow
aloft turning westerly. Some clouds are
likely along the coast, but skies should remain mostly sunny inland. Increasing onshore flow will begin a cooling
trend, as the surface thermal trough progresses eastward to near the Idaho
border. Coastal mixing gets limited by
cool low-level onshore flow, but mixing further inland should remain good. W-NW low-level winds will turn SW-W near the
top of the mixing layer.
The flow aloft turns SW on Sunday, as a stronger weather system
approaches the coast. Skies remain mostly
sunny with above-average temperatures.
Mixing should be good, especially east of the coast range, with onshore winds
across all zones.
Big changes come on Monday (Memorial Day). A Pacific cold front comes ashore, bringing cooler
and damp weather from NW to SE across the state. Mixing will be excellent with
brisk SW-W winds. Rainfall totals may
locally exceed .50” in the north coast range and Cascades with light showers
possibly extending across all zones by evening.
2. DISPERSION
FRIDAY
Zone 601, 602,
603 and 612 (North Coast Range):
MORNING
Mixing height
below 1000 ft early rising to 1500 - 2500 ft by late morning.
Transport wind NW
to N at 6 - 10 mph.
Surface wind NW
to N at 4 - 8 mph.
AFTERNOON
Mixing height
2300 - 3300 ft.
Transport wind similar to morning.
Surface wind similar to morning.
EVENING
Mixing height
1000 - 1700 ft.
Transport wind similar to afternoon.
Surface wind WNW
to NNW at 6 - 10 mph.
Zone 605-611 and
639 (North Cascades):
MORNING
Mixing height
below 1000 ft early rising to 2000 - 3000 ft by late morning.
Transport wind
WNW to NNW at 6 - 10 mph.
Surface wind NW
to N at 4 - 8 mph.
AFTERNOON
Mixing height
rising to 4000 - 5000 ft.
Transport wind NW
to N at 8 - 12 mph.
Surface wind similar to morning.
EVENING
Mixing height
2000 - 3000 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 by late morning.
Transport wind
NNW to NNE at 9 - 15 mph.
Surface wind NNW
to NNE at 6 - 10 mph.
AFTERNOON
Mixing height
2100 - 3100 ft.
Transport wind similar to morning.
Surface wind similar to morning.
EVENING
Mixing height
1000 - 1700 ft.
Transport wind similar to afternoon.
Surface wind NW
to N at 6 - 10 mph.
Zone 616-623
(South Cascades):
MORNING
Mixing height
below 1000 ft early rising to 2000 - 3000 ft by late morning.
Transport wind NW
to NNE at 6 - 10 mph.
Surface wind NW
to NNE at 4 - 8 mph.
AFTERNOON
Mixing height
rising to 4000 - 5000 ft.
Transport wind similar to morning.
Surface wind similar to morning.
EVENING
Mixing height
2000 - 3000 ft.
Transport wind similar to afternoon.
Surface wind similar to afternoon.
OUTLOOK:
SATURDAY
Mixing height
below 1000 ft early rising to 1800 to 2800 ft by late morning rising to 3200 to
4200 ft during the afternoon. Transport
wind NW to N at 4 - 8 mph. Surface wind
light and variable during the morning becoming WNW to NNW at 4 - 8 mph during
the afternoon.
SUNDAY
Mixing height
below 1000 ft early rising to 2200 to 3200 ft by late morning rising to 3400 to
4400 ft during the afternoon. Transport
wind light and variable during the morning becoming W to NW at 6 - 10 mph
during the afternoon. Surface wind light
and variable during the morning becoming W to NW at 4 - 8 mph during the
afternoon.
MONDAY
In the Coast
Range mixing height below 1000 ft early rising to 1900 to 2900 ft by late
morning rising above 5000 ft during the afternoon. In the Cascades mixing height below 1000 ft
early rising to 2800 to 3800 ft by late morning rising above 5000 ft during the
afternoon. Transport wind SSW to SW at
16 - 26 mph. Surface wind SSW to WSW at
6 - 12 mph.
3. BURNING
INSTRUCTIONS FOR ALL ZONES IN THE WESTERN OREGON AREA
- Valid for burning done Friday, May 22,
2026.
=================================================================
Coast Range
***Avoid
ignitions before 10 a.m. in all zones.***
Zone 601 and 612
Units should be
1200 tons or less, spaced 12 miles apart, and 12 miles from downwind
SSRAs. Higher tonnage is possible south
of Waldport in Zone 612. Call the
forecaster.
Zone 602, 603,
and 616 east of R9W
Units should be
600 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs. Limit tonnage north of Forest Grove/Hillsboro
or Sheridan/Willamina in Zone 602. Higher
tonnage is possible south of T17S in Zone 603.
Call the forecaster.
Zone 615, 618,
and 619
Use standard
guidance matrix. (See section 5 below.)
Avoid burning directly upwind of the North Bend/Coos Bay SSRA.
Zone 616 west of
R8W
Units should be
900 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs.
Zone 620
Units should be
300 tons or less, spaced 12 miles apart, and 12 miles from downwind SSRAs. Higher tonnage is possible south of the Rogue
River. Call the forecaster.
Cascades
Zone 605, 606,
607, 608, 639, 611, 616, 617, and 623
Use standard
guidance matrix - see section 5 below.
Ensure adequate distance from downwind SSRAs for smoke to
dissipate. Verify transport winds away
from SSRA if burning within 10 miles of the SSRA in Zone 605 and 606. South of T30S in Zone 616 units should be
1000 tons or less, spaced 6 miles apart.
South of T30S in Zone 617 units should be 1000 tons or less, spaced 6
miles apart.
Zone 610
Units should be
1200 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs.
Zone 620 and 622
Units should be
750 tons or less, spaced 6 miles apart, and 8 miles from downwind SSRAs.
Siskiyous
***Avoid
ignitions before 10 a.m.***
Use standard
guidance matrix - see section 5 below. Ensure adequate distance from downwind
SSRAs for smoke to dissipate.
==============================================================
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.