THIS AVALANCHE ADVISORY EXPIRED ON December 20, 2017 @ 6:17 am
Avalanche Advisory published on December 19, 2017 @ 6:17 am
Issued by Jeff Thompson - Idaho Panhandle Avalanche Center

Selkirks/Cabinets

bottom line

A major winter storm has arrived and is dropping a large amount of snow on a very weak snowpack. Expect to see wide spread avalanche activity in the backcountry for the next 24 hours. We could see snow today falling at a rate of 1-2'' an hour with totals approaching a meter in higher elevations.  Careful snowpack evaluation, cautious route finding and conservative decision making will be essential.  Human triggered avalanches are likely on slopes above 30 degrees. 

How to read the advisory

Selkirks/Cabinets

How to read the advisory

A major winter storm has arrived and is dropping a large amount of snow on a very weak snowpack. Expect to see wide spread avalanche activity in the backcountry for the next 24 hours. We could see snow today falling at a rate of 1-2'' an hour with totals approaching a meter in higher elevations.  Careful snowpack evaluation, cautious route finding and conservative decision making will be essential.  Human triggered avalanches are likely on slopes above 30 degrees. 

4. High

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Above Treeline
Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.

4. High

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Near Treeline
Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.

3. Considerable

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Below Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
    Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.
Avalanche Problem 1: Storm Slab
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A heavy and dense storm slab fueled by strong winds and heavy snowfall will form over the next 48 hours on a weak snowpack. 

Avalanche Problem 2: Wind Slab
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With high winds from changing directions, expect to see newly formed wind slabs near ridge tops and leeward slopes. avoid areas of recently wind deposited snow.

Weather and CURRENT CONDITIONS
Weather observations from the Region
0600 temperature: 19 deg. F.
Max. temperature in the last 24 hours: 26 deg. F.
Average wind direction during the last 24 hours: NW
Average wind speed during the last 24 hours: 18 mph
Maximum wind gust in the last 24 hours: 71 mph
New snowfall in the last 24 hours: 2-10'' inches
Total snow depth: 40'' inches
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Tuesday Tuesday Night Wednesday
Weather: Snow Rain / Snow Snow then clearing
Temperatures: 34 deg. F. 29 deg. F. 29 deg. F.
Wind Direction: ENE SW SW
Wind Speed: 10 mph 8-10 mph 6-8 mph
Expected snowfall: 3-6'' in. 2-4'' in. .5-3'' in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Snow Snow Snow then clearing
Temperatures: 30 deg. F. 21 deg. F. 24 AM > 16 PM deg. F.
Wind Direction: ENE SW SW
Wind Speed: 10-15 G30 11-15 8-10
Expected snowfall: 13-20'' in. 3-7'' in. 1-2'' before 10AM in.
Disclaimer

Avalanche conditions change for better or worse continually. Backcountry travelers should be prepared to assess current conditions for themselves, plan their routes of travel accordingly, and never travel alone. Backcountry travelers can reduce their exposure to avalanche hazards by utilizing timbered trails and ridge routes and by avoiding open and exposed terrain with slope angles of 30 degrees or more. Backcountry travelers should carry the necessary avalanche rescue equipment such as a shovel, avalanche probe or probe ski poles, a rescue beacon and a well-equipped first aid kit.  For a recorded version of the Avalanche Advisory call (208)765-7323.