SMOKE MANAGEMENT FORECAST AND INSTRUCTIONS

SALEM FORESTRY WEATHER CENTER

OREGON DEPARTMENT OF FORESTRY

 

ISSUED: Friday, October 24, 2014       2:35 PM      Tom Jenkins

 

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


SHORT-TERM DISCUSSION

An upper level trough will move over northern Oregon Saturday, making the atmosphere less stable. Mixing will be excellent throughout the day, and isolated thunderstorms may form near the Cascades. A surface cold front will get caught in the Cascades Saturday afternoon, bringing spotty showers and strong onshore flow to the western zones.

EXTENDED DISCUSSION

The weather pattern will stabilize Sunday, as an upper level ridge builds over the area and onshore flow weakens dramatically. A surface ridge will develop, capping mixing levels. Winds will be light, primarily influenced by local terrain. Inversions will form quickly after sunset, as warmer air aloft moves in from the south behind the upper level ridge. Monday, a thermal trough will form over western Oregon, shifting winds to offshore flow and further restricting mixing.

The upper level ridge will begin to flatten Monday evening, allowing the jet stream to carry it east of the region. Winds will slowly shift to onshore flow Tuesday, as an upper level trough deepens offshore of Oregon. As it passes by, a surface cold front will weaken and dissipate over western zones. This will improve mixing conditions and bring isolated showers Tuesday afternoon.

 

2.  DISPERSION

 

SATURDAY

 

Zone 640, 642, and 644 West of R35E:

Mixing height below 500 ft early rising to 3000 - 4000 ft by late morning.  Afternoon mixing height rises above 5000 ft then lowers to 2000 - 3000 ft during the evening.

 

Transport wind SSW to SW at 18 - 32 mph during the morning.  Transport wind increases to SSW to SW at 25 - 43 mph during the afternoon then decreases to SSW to SW at 15 - 29 mph during the evening.

 

Surface wind S to SW at 15 - 25 mph during the morning and afternoon.  Surface wind decreases to SSW to SW at 10 - 20 mph during the evening.

 

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

Mixing height below 500 ft early rising to 2500 - 3500 ft by late morning.  Afternoon mixing height rises above 5000 ft then lowers to 2500 - 3500 ft during the evening.

 

Transport wind SSE to SSW at 18 - 32 mph during the morning.  Transport wind increases to SSE to SSW at 22 - 38 mph during the afternoon and evening.

 

Surface wind SE to S at 10 - 20 mph during the morning.  Surface wind increases to SSE to SSW at 15 - 25 mph during the afternoon and evening.

 

OUTLOOK:

 

SUNDAY

In the west mixing height 4000 to 5000 ft throughout the day.  In the east mixing height below 1000 ft early rising above 5000 ft by late morning and through the afternoon.  Transport wind WSW to NW at 6 - 12 mph.  Surface wind WSW to NW at 4 - 8 mph.

 

MONDAY

Mixing height below 1000 ft early rising to 3200 to 4200 ft by late morning rising above 5000 ft during the afternoon.  Transport wind ESE to S at 6 - 10 mph during the morning becoming SSE to SSW at 8 - 12 mph during the afternoon.  Surface wind E to SE at 4 - 8 mph.

 

TUESDAY

Mixing height 2000 to 3000 ft during the morning rising above 5000 ft during the afternoon.  Transport wind SW to WSW at 10 - 22 mph.  Surface wind SSE to SSW at 9 - 15 mph.

 

3.  BURNING INSTRUCTIONS FOR NORTHEAST OREGON ZONES 637-646

    The following considerations should be adhered to in addition to

    the requirements of the Oregon Smoke Management Plan. These

    Instructions are valid for burning conducted on Saturday, October 25, 2014.

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

 

Zone 640, 642, and 644 West of R35E:

Avoid ignitions within 12 miles to the SSW through SW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 12 miles to the SSW through WNW in or near drainages leading to SSRAs.  No additional restrictions necessary. 

 

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

Avoid ignitions within 12 miles to the SSE through SSW of SSRAs.  For units that will smolder significantly through the night avoid burning within at least 20 miles in all directions of SSRAs. 

 

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

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 before

    8 a.m. and between 2 to 3 p.m.

 

    This forecast is available on the Internet at:

      http://oregon.gov/ODF/FIRE/fire.shtml/#Smoke_Management_Information

 

    Please ensure your units have been planned and accomplished by checking:

      http://oregon.gov/ODF/FIRE/SMP/dailysmoke.shtml