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Burn Recommendations

Last Updated: 2021-04-13 12:40:06.940753 MST
Idaho
No Restrictions 
Montana
No Restrictions 

Meteorology/Dispersion Discussion

Last Updated: 2021-04-13 14:01:07.769721 MST

Wednesday 14 April Discussion Northeasterly flow aloft and at the surface will continue today with a broad trough of low pressure over the Northern Rockies and Plains and another low pressure center developing in the Great Basin. Precipitation potential will be focused in southern Idaho and central/eastern Montana leaving many of the western airsheds dry. On Friday and Saturday a ridge of high pressure will overspread the Pacific Northwest including northern Idaho and western Montana with a more stable pattern bringing limited smoke dispersion in the western airsheds. This will be interrupted on Sunday with a fast-moving trough of low pressure that will move through the Northern Rockies from north to south with only slightly better smoke dispersion but also a quick shot of moisture. Thereafter, the first half of next week offers relatively drier northwest flow aloft under broad high pressure ridging with limited smoke dispersion.

GOOD smoke dispersion in Idaho and western Montana Today with northeast flow aloft and at the surface. Isolated showers. GOOD smoke dispersion in central/eastern Montana with northeast flow aloft and at the surface.

MARGINAL-GOOD smoke dispersion in Idaho and western Montana Thursday with north-northeast flow aloft and at the surface. MARGINAL-GOOD smoke dispersion in central/eastern Montana with weak northeast flow aloft. Light east-northeast surface winds. Isolated showers along the Continental Divide and in the mountains of southern Montana. 

MARGINAL smoke dispersion in Idaho and western Montana Friday with northeast flow aloft and at the surface. MARGINAL smoke dispersion in central/eastern Montana with northeast flow aloft. Light north-northeast surface winds. Isolated showers in the mountains of southern Montana. 

POOR-MARGINAL smoke dispersion in Idaho and western Montana Saturday with northeast flow aloft/high pressure ridging. MARGINAL-GOOD smoke dispersion in central/eastern Montana with northerly flow aloft. Light surface winds in central Montana but moderate northeast surface winds in eastern Montana.

MARGINAL smoke dispersion in Idaho and western Montana Sunday with  MARGINAL-GOOD smoke dispersion in central/eastern Montana with northwest flow aloft/fast moving trough of low pressure. Light northeast surface winds.  Widespread showers in western Montana. GOOD-EXCELLENT smoke dispersion in central/eastern Montana with northwest flow aloft/fast moving upper level trough. Light to moderate northerly surface winds. Scattered showers.

POOR-MARGINAL smoke dispersion in Idaho and western Montana Monday with northwest flow aloft/weak trough of low pressure. Isolated rain showers. GOOD smoke dispersion in central/eastern Montana with northwest flow aloft. Light northeast surface winds. Scattered showers.

Thursday 15 April Dispersion Forecast

MONTANA:

Northwest (AS 1, 2): GOOD.

West Central (AS 3A, 3B, 4, 5, 6): GOOD.

Southwest (AS 7, 8A, 8B):  GOOD.

Central/Eastern (AS 9, 10): GOOD.


IDAHO:

North (AS 11): MARGINAL.

North Central (AS 12A, 12B, 13): MARGINAL.

West Central (AS 14, 15): MARGINAL.

East Central (AS 16, 17):  MARGINAL.

Southeast (AS 18, 19, 20): MARGINAL.

Southwest (AS 21, 22, 23, 24): MARGINAL.

Prepared by Coleen Haskell, NRCC Meteorologist