SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Monday, May 18, 2026 2:30 PM Sherri Pugh

1. DISCUSSION AND FORECAST FOR THE WESTERN OREGON AREA FORECAST ZONES 601-623 and 639

Upper-level ridging will dominate the weather for the week ahead. Flow aloft will be from NW with ridging offshore and a weak trough moving over the ridge late on Tuesday. Isolated showers are possible far north and late. Winds will come from WNW-NNW. Temperatures will be near or above average. Mixing heights will be fair to good.

EXTENDED DISCUSSION

Dry weather on Wednesday will have NW flow aloft with upper-level ridging offshore. Winds will generally come from N. Temperatures will rise above average and mixing heights will be fair to good.

Thursday will be the warmest day of the week for many with dry conditions. Flow aloft will continue from NW. Mixing heights will be fair to poor for coastal zones and good for Cascades zones. Light winds will come mostly from N at the surface and from NW-N for transport winds.

The upper-level ridge begins to flatten and weaken some on Friday with light W flow aloft. Winds will come from N on the coast and from SW-NW for the Cascades and more variable at the surface. Temperatures will be above average. Mixing heights will be fair at the coast and higher inland.

2. DISPERSION

TUESDAY

Zone 601, 602, 603 and 612 (North Coast Range):

MORNING

Mixing height below 500 ft early rising to 2500 - 3500 ft by late morning.

Transport wind W to NW at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

AFTERNOON

Mixing height 2500 - 3500 ft.

Transport wind WNW to NNW at 6 - 10 mph.

Surface wind increases to WNW to NNW at 4 - 8 mph.

EVENING

Mixing height 1000 - 2000 ft.

Transport wind NW to N at 6 - 10 mph.

Surface wind similar to afternoon.

Zone 605-611 and 639 (North Cascades):

MORNING

Mixing height below 500 ft early rising to 3500 - 4500 ft by late morning.

Transport wind W to NW at 6 - 10 mph.

Surface wind WNW to NNW at 4 - 8 mph.

AFTERNOON

Mixing height 3500 - 4500 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.

Zone 615-620 (South Coast Range):

MORNING

Mixing height below 500 ft early rising to 2500 - 3500 ft by late morning.

Transport wind N to NE at 6 - 10 mph.

Surface wind light and variable and controlled by local terrain.

AFTERNOON

Mixing height 2500 - 3500 ft.

Transport wind similar to morning.

Surface wind increases to NW to N at 6 - 10 mph.

EVENING

Mixing height 1000 - 1500 ft.

Transport wind NNW to NNE at 6 - 10 mph.

Surface wind similar to afternoon.

Zone 616-623 (South Cascades):

MORNING

Mixing height below 500 ft early rising to 2500 - 3500 ft by late morning.

Transport wind NW to N at 4 - 8 mph.

Surface wind light and variable and controlled by local terrain.

AFTERNOON

Mixing height 3500 - 4500 ft.

Transport wind WNW to NNW at 6 - 10 mph.

Surface wind increases to WNW to NNW at 4 - 8 mph.

EVENING

Mixing height 2000 - 3000 ft.

Transport wind NW to N at 6 - 10 mph.

Surface wind similar to afternoon.

OUTLOOK:

WEDNESDAY

Mixing height below 1000 ft early rising to 2400 to 3400 ft by late morning and through the afternoon. Transport wind NNW to NNE at 4 - 8 mph. Surface wind light and variable during the morning becoming NNW to NNE at 4 - 8 mph during the afternoon.

THURSDAY

Mixing height below 1000 ft early rising to 1900 to 2900 ft by late morning rising to 2800 to 3800 ft during the afternoon. Transport wind N to NE at 4 - 8 mph. Surface wind light and variable.

FRIDAY

Mixing height below 1000 ft early rising to 1400 to 2400 ft by late morning rising to 2800 to 3800 ft during the afternoon. Transport wind light and variable during the morning becoming NW to N at 4 - 8 mph during the afternoon. Surface wind light and variable.

3. BURNING INSTRUCTIONS FOR ALL ZONES IN THE WESTERN OREGON AREA

- Valid for burning done Tuesday, May 19, 2026.

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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, 616, 618, 619, and 620

Use standard guidance matrix. (See section 5 below.) Avoid burning directly upwind of the North Bend/Coos Bay SSRA.

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. From T12S through T17S in Zone 608 units should be 1200 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. East of R2W in Zone 622, use standard guidance matrix - see section 5 below.

Siskiyous

Use standard guidance matrix - see section 5 below. Ensure adequate distance from downwind SSRAs for smoke to dissipate.

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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.