SMOKE MANAGEMENT
FORECAST AND INSTRUCTIONS
SALEM FORESTRY
WEATHER CENTER
OREGON DEPARTMENT
OF FORESTRY
ISSUED: Thursday,
May 8, 2025
2:30 PM Pete Parsons
1. DISCUSSION AND
FORECAST FOR THE WESTERN OREGON AREA FORECAST ZONES 601-623 and 639
SHORT-TERM DISCUSSION
After a chilly start, sunshine is helping temperatures climb
to near or above average this afternoon with good ventilation conditions. On
Friday, sunshine and a dry SW flow aloft will lift temperatures to 10-15°F
above average, with good afternoon mixing.
Generally light winds should turn mostly SW-W.
EXTENDED DISCUSSION
An approaching upper-level trough increases the SW flow
aloft on Saturday. Expect more clouds
and SW-NW winds, as another dry cold front comes ashore in the afternoon, cooling
temperatures slightly and suppressing mixing for the coastal zones.
A potent upper-level trough brings widespread showers and
much cooler temperatures on Sunday.
Rainfall totals near .10” will be common from the coast to the Cascade
crest with lighter and spotty showers in central Oregon. Snow levels will drop to near 5000 feet with
much cooler air aloft supporting excellent mixing. Brisk transport winds turn mostly SW-W.
Cool and showery conditions continue through Monday, with an
upper-level trough parked over the Pacific Northwest. Additional rainfall totals near .10” are
likely for most areas. Temperatures cool
to about 10°F below average with snow levels at 4-5000 feet. Mixing remains excellent with brisk transport
winds turning NW across all but perhaps the interior southern zones, which may have
SW-W winds.
Slow drying and warming is expected Tuesday and Wednesday with
NW winds for most areas.
2. DISPERSION
FRIDAY
Zone 601, 602,
603 and 612 (North Coast Range):
MORNING
Mixing height
below 1000 ft early rising to 2300 - 3300 ft by late morning.
Transport wind
light and variable and controlled by local terrain.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing height
3000 - 4000 ft.
Transport wind
increases to WSW to WNW at 4 - 8 mph.
Surface wind similar to morning.
EVENING
Mixing height
1000 - 1700 ft.
Transport wind W
to NW at 6 - 10 mph.
Surface wind
increases to W to NW at 4 - 8 mph.
Zone 605-611, 639
and 616-623 (North and South Cascades):
MORNING
Mixing height
below 1000 ft early rising to 2300 - 3300 ft by late morning.
Transport wind
light and variable and controlled by local terrain.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing height
rising above 5000 ft.
Transport wind
increases to SW to W at 4 - 8 mph.
Surface wind similar to morning.
EVENING
Mixing height
1700 - 2700 ft.
Transport wind
shifts to WNW to NNW at 6 - 10 mph.
Surface wind
increases to WNW to NNW at 4 - 8 mph.
Zone 615-620
(South Coast Range):
MORNING
Mixing height
below 1000 ft early rising to 2000 - 3000 ft by late morning.
Transport wind
light and variable and controlled by local terrain.
Surface wind
light and variable and controlled by local terrain.
AFTERNOON
Mixing height
2700 - 3700 ft.
Transport wind
increases to WSW to NW at 4 - 8 mph.
Surface wind
increases to W to NW at 4 - 8 mph.
EVENING
Mixing height
1000 - 1700 ft.
Transport wind W
to NW at 6 - 10 mph.
Surface wind similar to afternoon.
OUTLOOK:
SATURDAY
Mixing height
below 1000 ft early rising to 2200 to 3200 ft by late morning rising to 3600 to
4600 ft during the afternoon. Transport wind WSW to WNW at 5 - 9 mph. Surface wind WSW to WNW at 4 - 8 mph.
SUNDAY
Mixing height
3200 to 4200 ft during the morning rising above 5000 ft during the
afternoon. Transport wind SW to W at 10
- 18 mph. Surface wind SW to W at 6 - 10
mph during the morning becoming SW to W at 10 - 16 mph during the afternoon.
MONDAY
Mixing height
3200 to 4200 ft during the morning rising above 5000 ft during the
afternoon. Transport wind WNW to NNW at
6 - 10 mph. Surface wind WNW to NNW at 4
- 8 mph.
3. BURNING
INSTRUCTIONS FOR ALL ZONES IN THE WESTERN OREGON AREA
- Valid for burning done Friday, May 9,
2025.
=================================================================
Coast Range
Zone 601 and 612
Units should be
1000 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs. Restrict units in or near corridors to 500
tons or less.
Zone 602 and 603
Units should be
400 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs. Limit burning in or near corridors. Higher tonnage is possible south of the
Siuslaw River in Zone 603. Call the
forecaster.
Zone 615 and 616
west of R8W
Units should be
1200 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.
Zone 616 east of
R9W
Units should be
750 tons or less, spaced 8 miles apart, and 10 miles from downwind SSRAs.
Zone 618 and 619
Use standard guidance matrix. (See section 5 below.)
Zone 620
Units should be
300 tons or less, spaced 8 miles apart, and 10 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 1200 tons or less, spaced 3 miles apart.
Zone 611
Units should be
1500 tons or less, spaced 3 miles apart, and 5 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.