THIS AVALANCHE ADVISORY EXPIRED ON January 29, 2020 @ 6:36 am
Avalanche Advisory published on January 28, 2020 @ 6:36 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

With a variety of surfaces out there, including crusts up to 6000ft, expect to trigger wind slabs and storm slabs in the new snow that fell yesterday and today.  The avalanche danger will stay elevated over the next couple days as we are predicted to keep recieving snow.  New snow takes a couple days to stabilize after a storm. 

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

With a variety of surfaces out there, including crusts up to 6000ft, expect to trigger wind slabs and storm slabs in the new snow that fell yesterday and today.  The avalanche danger will stay elevated over the next couple days as we are predicted to keep recieving snow.  New snow takes a couple days to stabilize after a storm. 

3. Considerable

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Above Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

2. Moderate

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

2. Moderate

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Below Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
    Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
Avalanche Problem 1: Storm Slab
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With snow levels hovering around 4000ft last night, expect snow densities to be heavier at the lower elevations and lighter up high. We picked up new snow last night and expect to recieve another 4 to 8 today. Give the pack some time to stabilize and settle before looking to step it out into big terrain.  

Avalanche Problem 2: Wind Slab
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New storm snow and winds strong enough to transport snow have created sensitive wind slabs on the NW-N-E-SE ridgelines.  Look for chalky colored pillows that sound hollow.  If you are experiencing cracking or whumphing these are signs that the wind slabs are being reactive. The photo below illustrates a shooting crack on a wind slab from the weight of a person.  

Avalanche Problem 3: Persistent Slab
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We still have hidden dragons in the snowpack. They are getting harder and harder to find, but we must remain vigilant in checking for them. New storm snow with heavy, rapid loading has the potential to wake these layers up.  On Sunday up Burke at 6300ft we found a reactive buried surface hoar layer as well as the graupel layer from the first week of January still propegating in pit tests!  The only way to know if these are at your location is to dig down and see.  I'm not ready to trust them yet!

Weather and CURRENT CONDITIONS
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 and Patchy fog then rain Chance rain/snow then slight chance snow chance snow then rain/snow likely
Temperatures: 38 deg. F. 32 deg. F. 39 deg. F.
Wind Direction: SW SW S
Wind Speed: 9 5-7 3-6
Expected snowfall: trace in. trace in. trace in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Heavy Snow and Areas Freezing Fog Snow likely then chance snow chance snow
Temperatures: 30 deg. F. 24 deg. F. 30 deg. F.
Wind Direction: SW W SW
Wind Speed: 13-16, G25 8-10 11-14
Expected snowfall: 4-8 in. 1-3 in. <.5 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.

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