THIS AVALANCHE ADVISORY EXPIRED ON February 28, 2018 @ 6:52 am
Avalanche Advisory published on February 27, 2018 @ 6:52 am
Issued by Jeff Thompson - Idaho Panhandle Avalanche Center

Selkirks/Cabinets

bottom line

The new snow across the Selkirk and Cabinet mountains have made for some powdery conditions! Be aware of soft slab potential near and above treeline. The light snow on the surface isn't a big concern right now, but we're looking at 15-20'' more by this weekend. As more snow falls, your internal 'red light' should be getting brighter. Expect the avalanche danger to increase over the next couple days.

How to read the advisory

Selkirks/Cabinets

How to read the advisory

The new snow across the Selkirk and Cabinet mountains have made for some powdery conditions! Be aware of soft slab potential near and above treeline. The light snow on the surface isn't a big concern right now, but we're looking at 15-20'' more by this weekend. As more snow falls, your internal 'red light' should be getting brighter. Expect the avalanche danger to increase over the next couple days.

2. Moderate

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Above Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

2. Moderate

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Near Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Storm Slab
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The new snow is in the form of a soft slab right now which is likely to change over the next couple days. As more snow falls, the current soft slab will stiffen up. We'll have to wait to see how this next snow comes in to determine exactly what it means for stability.  Start to become more conservative with your decisions making as more snow falls.

Avalanche Problem 2: Persistent Slab
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We have to keep persistent weaknesses in the back of our minds. There are (at least) 3 buried layers that concern me. All 3 of these layers are deep in the snowpack. For the most part, they have been lying dormant but are capable of waking up at any point. The 3 layers are: 1. Thanksgiving crust 2. Dec 16 surface hoar 3. MLK surface hoar.  There are other instabilities in the snowpack but these 3 layers are widespread and are for the most part still intact. Keep deep instabilities in you brain when making decisions. 

Weather and CURRENT CONDITIONS
Weather observations from the Region
0600 temperature: 22 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: 15 mph
Maximum wind gust in the last 24 hours: 54 mph
New snowfall in the last 24 hours: 2 inches
Total snow depth: 136 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 Snow Snow
Temperatures: 34 deg. F. 27 deg. F. 34 deg. F.
Wind Direction: SW SW SW
Wind Speed: 6-9 5-7 3-5
Expected snowfall: 1'' in. 1'' in. >1'' in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Snow Snow Snow
Temperatures: 24 deg. F. 20 deg. F. 28 deg. F.
Wind Direction: SW SW SW
Wind Speed: 18-20 10-12 14-16
Expected snowfall: 2-4'' in. 1-3'' in. 1-3'' 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.