SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Friday, December 20, 2019       2:40 PM      Pete Parsons

 

************************** End of Season ****************************

This is the last written weather forecast and set of prescribed-burning instructions for winter season.  The ODF forecast office will remain open Monday through Friday (except holidays), but beginning Monday, December 23rd, you will need to call the forecast office at 503-945-7401, for smoke clearance or for smoke-related questions.

We plan to resume issuing written forecasts/instructions, when prescribed burning picks up in the spring but may resume them sooner, if there is enough demand.

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1.  DISCUSSION AND FORECAST FOR SOUTH CENTRAL OREGON ZONES 624 AND 625

 

SHORT-TERM DISCUSSION

A very moist frontal zone has stalled across Washington and NW Oregon.  South of the front, skies are cloudy, with brisk southerly winds pushing snow levels to near 7000 feet.

A potent and slow-moving cold front will swing onshore Saturday.  South-central Oregon will remain in the warm sector of the storm, with increasing clouds, brisk S-SW winds, and excellent daytime mixing.  Snow levels will generally stay above 5000 feet.

The cold front will bring areas of light rain and snow Saturday night and Sunday, as the cold front finally moves across the region and drops snow levels back to near the basin floor.  South winds will turn westerly Sunday afternoon with fair-to-good daytime mixing.

EXTENDED DISCUSSION

A cool upper-level trough may produce a few showers on Monday, before weakening on Tuesday.  Cool air aloft will provide good daytime mixing with light winds on Monday.  Skies should turn partly sunny on Tuesday with light SE-SW winds and fair-to-good daytime mixing.

2.  DISPERSION

 

SATURDAY

 

Mixing height above 5000 ft throughout the day.  Mixing height lowers to 2500 - 3500 ft during the evening.

 

Transport wind S to SSW at 20 - 36 mph during the morning.  Transport wind increases to SSW to SW at 23 - 41 mph during the afternoon then decreases to SSW to SW at 15 - 29 mph during the evening.

 

Surface wind SSE to SSW at 15 - 25 mph during the morning and afternoon.  Surface wind decreases to S to SW at 9 - 15 mph during the evening.

 

OUTLOOK:

 

SUNDAY

Mixing height 3200 - 4200 ft during the morning rising above 5000 ft during the afternoon.  Transport wind SSE to SSW at 10 - 18 mph during the morning becoming SSE to S at 15 - 25 mph during the afternoon.  Surface wind SE to SSW at 6 - 10 mph.

 

MONDAY

Mixing height 2500 - 3500 ft during the morning rising above 5000 ft during the afternoon.  Transport wind light and variable during the morning becoming ESE to S at 4 - 8 mph during the afternoon.  Surface wind light and variable.

 

TUESDAY

Mixing height 1500 - 2500 ft during the morning rising to 4000 - 5000 ft during the afternoon.  Transport wind SSE to SSW at 6 - 10 mph.  Surface wind SE to SSW at 5 - 9 mph.

 

3.  BURNING INSTRUCTIONS FOR ZONES 624 AND 625 INCLUDING THE WALKER

    RANGE PORTION OF ZONE 624

    - Valid for burning done Saturday and Sunday, December 21 and 22, 2019.

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For Saturday:

 

Follow standard guidance matrix - see section 5 below - for burning units to the S through SW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 5 miles to the SSE through SW in or near drainages leading to SSRAs.  Care needed in selecting units as smoke will likely fumigate along the ground in wind prone areas.  No additional restrictions necessary. 

 

For Sunday:

 

Follow standard guidance matrix - see section 5 below - for burning units to the SE through W of SSRAs.  Watch for shifting transport winds.  No additional restrictions necessary. 

 

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4.  SPECIAL NOTE:

 

    The smoke management forecaster is available at (503)

    945-7401.  The smoke management forecaster is available

    to discuss specific burns.  The duty forecaster phone

    number is (503) 945-7401. Please call this number and

    not individual's numbers to discuss daily burning. Please

    avoid calling between 1:30 to 2:45 p.m.

 

    http://www.odf.state.or.us/DIVISIONS/protection/fire_protection/Daily/lmt.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.

    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 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.