SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

ISSUED: Monday, April 22, 2024 2:30 PM Gary Votaw

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

SHORT-TERM DISCUSSION

On Tuesday an upper-level ridge will be over the region with a weak trough offshore providing WSW flow aloft. The weather will be mostly sunny and warm, temperatures still 5-10^oF above seasonal normals. After low early morning mixing heights conditions will become quite good by the afternoon. Transport winds will turn W-NW during the afternoon and evening for the western zones but remaining light and mostly variable in the east.

EXTENDED DISCUSSION

The trough will be mainly north of Oregon on Wednesday with only subtle influences on East Oregon. Temperatures will be just a few degrees lower under mostly sunny skies. Low early morning mixing heights become very good by late morning through the afternoon with W transport winds.

A stronger and developing trough will approach offshore on Thursday to give a chance of light showers during the day, still partly sunny and temperatures falling to near seasonal. Light showers will become likely Thursday night for less than .10” of moisture. Mixing conditions will again be very good with light W transport winds.

The trough will pass over the state on Friday for showers still likely and a chance of thunderstorms. Mixing heights will be very good all day with W transport winds.

2. DISPERSION

TUESDAY

Zone 640, 642, and 644 West of R35E:

Low early morning mixing height below 1000 ft rising to 2900 - 3900 ft during the morning. Mixing height rises to above 5000 ft during the afternoon then lowers to 4000 - 5000 ft during the evening.

Transport wind S to SW at 6 - 12 mph during the morning. Transport wind shifts to WSW to WNW at 9 - 15 mph during the afternoon and shifts to NW to N at 6 - 12 mph during the evening.

Surface wind light and variable and controlled by local terrain during the morning. Surface wind increases to SW to W at 5 - 9 mph during the afternoon then shifts to NW to N at 4 - 8 mph during the evening.

Zone 637, 643, 645, 646, and 644 East of R34E:

Mixing height 2300 - 3300 ft during the morning. Mixing height rises to above 5000 ft during the afternoon then lowers to 4100 - 5000 ft during the evening.

Transport wind SE to SSW at 4 - 8 mph during the morning. Transport wind shifts to WSW to WNW at 5 - 9 mph during the afternoon then becomes light and variable and controlled by local terrain during the evening.

Surface wind ENE to ESE at 4 - 8 mph during the morning. Surface wind shifts to WNW to NNW at 6 - 12 mph during the afternoon then becomes light and variable and controlled by local terrain during the evening.

OUTLOOK:

WEDNESDAY

Mixing height below 1000 ft early rising to 3600 to 4600 ft by late morning rising above 5000 ft during the afternoon. Transport wind WSW to WNW at 6 - 10 mph during the morning becoming WSW to WNW at 10 - 18 mph during the afternoon. Surface wind light and variable during the morning becoming NW to NNW at 8 - 14 mph during the afternoon.

THURSDAY

Mixing height below 1000 ft early rising to 4300 to 5000 ft by late morning rising above 5000 ft during the afternoon. Transport wind WSW to WNW at 5 - 9 mph. Surface wind WSW to WNW at 5 - 9 mph.

FRIDAY

Mixing height 4500 to 5000 ft in the morning rising above 5000 ft during the afternoon. Transport wind WSW to WNW at 10 - 16 mph. Surface wind WSW to WNW at 12 - 22 mph during the morning becoming WNW to NNW at 6 - 12 mph during the afternoon.

3. BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646

- Valid for burning done Tuesday, April 23, 2024.

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Delay ignitions until 10 a.m. Zone 640, 642, and 644 West of R35E:

Follow standard guidance matrix - see section 5 below - for burning units in all directions of SSRAs. For units that will smolder significantly through the night avoid burning within at least 10 miles in all directions of SSRAs. Watch for shifting transport winds. No additional restrictions necessary.

Delay ignitions until 10 a.m. Zone 637, 643, 645, 646, and 644 East of R34E:

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4. SPECIAL NOTE:

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.