THIS AVALANCHE ADVISORY EXPIRED ON January 8, 2020 @ 6:37 am
Avalanche Advisory published on January 7, 2020 @ 6:37 am
Issued by Jeff Thompson - Idaho Panhandle Avalanche Center

Selkirks/Cabinets

bottom line

A strong winter storm is producing heavy snow and wind across the forecast area. 2 ft of snow is already on the ground (above 4500').  The rain/snow line is currently hovering around 3800-4000'. Dangerous avalanche conditions exist in the backcountry. Strong SW winds combined with new snow will create an unstable snowpack on all aspects above treeline. Travel in the backcountry is not recommended

How to read the advisory

Selkirks/Cabinets

How to read the advisory

A strong winter storm is producing heavy snow and wind across the forecast area. 2 ft of snow is already on the ground (above 4500').  The rain/snow line is currently hovering around 3800-4000'. Dangerous avalanche conditions exist in the backcountry. Strong SW winds combined with new snow will create an unstable snowpack on all aspects above treeline. Travel in the backcountry is not recommended

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.

2. Moderate

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Below Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
    Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.
Avalanche Problem 1: Storm Slab
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Dangerous avalanche conditions exist in the forecast zone above 3800' 12-24'' of new snow has already blanketed the region. Another 24'' of snow is expected in the next 30 hours. The new snow is falling on a snow surface that is condusive to avalanching. Stay clear of avalanche terrain, runnout zones or areas (roads and trails) under steep terrain.

Avalanche Problem 2: Deep Slab
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New snow is the chief concern in the snowpack right now, but it's worth noting the instabilities that existed before this snow arrived. The structure of the old snowpack (before this new snow) was poor and showing signs of instability. The new snow is going to add a lot of weight and stress to the the underlying snowpack. New snow avalanches could trigger deep instabilities and create large avalanches. The's a high probability of avalanches stepping down into old weak layers in the snowpack

Weather and CURRENT CONDITIONS
weather summary

We're in a strong winter storm! The unsettled weather is expected to keep up into the weekend (with a break on Thursday). Look for a drop in temperature starting on Wednesday afternoon. NOAA has forecasted for up to 52'' of snow by Satuarday,  (5000'-6000') for the Selkirk and Cabinet mountains. 

Weather observations from the Region
0600 temperature: 36 deg. F.
Max. temperature in the last 24 hours: 39 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 8-10 mph
Maximum wind gust in the last 24 hours: 21 mph
New snowfall in the last 24 hours: 4-24'' inches
Total snow depth: 30''-78'' inches
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Tuesday Tuesday Night Wednesday
Weather: Rain /Snow Rain / Snow Rain / Snow
Temperatures: 39 deg. F. 34 deg. F. 47 / dropping PM deg. F.
Wind Direction: SW SW SW
Wind Speed: 8-11 6-9 10-12
Expected snowfall: 1-2'' in. 1-2'' in. 0-2'' in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: SNOW SNOW SNOW
Temperatures: 27 deg. F. 27 deg. F. 26 and dropping deg. F.
Wind Direction: SW SW SW
Wind Speed: 34-36 33-36 G50 27-31
Expected snowfall: 8-12'' in. 5-9'' in. 2-4'' 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.