SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Tuesday, May 19, 2026 2:30 PM Gary Votaw

1. DISCUSSION AND FORECAST FOR NORTHEAST FORECAST AREA ZONES 637-646

SHORT-TERM DISCUSSION

On Wednesday flow aloft is weak and N in response to an offshore ridge for mostly sunny and seasonal conditions. Mixing conditions become excellent by afternoon with very light NW-N winds.

EXTENDED DISCUSSION

The ridge greatly weakens and moves onshore on Thursday and Friday, but lower-level ridging remains strong. Sunny skies remain and a slow warming trend begins, reaching 5-10^oF above normal by Friday. Mixing conditions remain excellent on both days with very light winds, favoring W-N.

Flow aloft turns WSW by Saturday but little or no change in conditions will be noted. Burning potential is still very good though with light and variable winds.

2. DISPERSION

WEDNESDAY

Mixing height below 1000 ft early rising to 4200 - 5000 ft during the morning. Mixing height rises above 5000 ft during the afternoon and evening.

Transport wind NW to N at 6 - 10 mph during the morning and afternoon. Transport wind increases to NNW to NNE at 11 - 21 mph during the evening.

Surface wind light and variable and controlled by local terrain during the morning. Surface wind increases to NW to N at 5 - 9 mph during the afternoon and evening.

OUTLOOK:

THURSDAY

Mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon. Transport wind NNW to NNE at 9 - 15 mph. Surface wind light and variable during the morning becoming NNW to NNE at 5 - 9 mph during the afternoon.

FRIDAY

Mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon. Transport wind light and variable during the morning becoming W to NNW at 5 - 9 mph during the afternoon. Surface wind light and variable.

SATURDAY

Mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon. Transport wind light and variable during the morning becoming WSW to WNW at 9 - 15 mph during the afternoon. Surface wind light and variable during the morning becoming WSW to NW at 4 - 8 mph during the afternoon.

3. BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646

- Valid for burning done Wednesday, May 20, 2026.

==================================================================

Follow standard guidance matrix - see section 5 below - for burning units to the NW through NNE of SSRAs. For units that will smolder significantly through the night avoid burning within at least 10 miles to the NW through NNE in or near drainages leading to SSRAs. Verify transport winds away from SSRAs if burning in any other direction. 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.