THIS AVALANCHE ADVISORY EXPIRED ON January 30, 2019 @ 6:38 am
Avalanche Advisory published on January 29, 2019 @ 6:38 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

Sunny weather and no new precipitation over the weekend has helped the snowpack stabilize, but there are still pockets of instability out there.  Heads up for isolated areas of buried surface hoar, especially in sheltered areas on the NW-N-NE aspects at the mid elevations.  Several human triggered avalanches were reported over the weekend on this buried persistent weak layer.

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

Sunny weather and no new precipitation over the weekend has helped the snowpack stabilize, but there are still pockets of instability out there.  Heads up for isolated areas of buried surface hoar, especially in sheltered areas on the NW-N-NE aspects at the mid elevations.  Several human triggered avalanches were reported over the weekend on this buried persistent weak layer.

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.

2. Moderate

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Below Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Persistent Slab
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The buried surface hoar is still lurking down there at the mid and lower elevations.  The likely spots to find it are sheltered areas such as widely spaced timber and draws.  It is still proving to be reactive in tests and was the cause of a couple human triggered avalanches in the region over the weekend.  Use safe travel habits as you are headed up and give the snow layers an assessment to check for this buried weak layer in the areas you are recreating in.  Unfortunately, the weather is lining up to have a repeat process with another cool and clear night tonight creating ideal conditions for surface hoar development.  

Avalanche Problem 2: Wind Slab
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With no new snow to transport recently and warmer temperatures, the wind slabs have had some time to bond.  Still give the ridges and ridgelines caution and look for pillowed, chalky, and hollow sounding snow.  In areas that these were present, they were still possible to release.  

recent observations

With the warm and stable weather this weekend, we have had reports that the glide on Tiger Peak slid.  There was also another report of a human triggered avalanche up Burke over the weekend that released on the buried surface hoar layer.  With the warmer weather on Saturday, there is lots of evidence out there that the wet slide potential increased on the southern aspects with pinwheels and the debris from small loose wet slides.  Temperatures look to be a little cooler over the next to days, but still keep that in mind when on the sourthern aspects.  Thanks to everyone who sent in observations and keep them coming.  

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: Sunny Mostly Clear Partly Sunny
Temperatures: 34 deg. F. 20 deg. F. 34 deg. F.
Wind Direction: NE E SE
Wind Speed: 5-7 Light Calm
Expected snowfall: 0 in. 0 in. 0 in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Sunny Mostly Clear Partly Sunny
Temperatures: 28 deg. F. 16 deg. F. 27 deg. F.
Wind Direction: SE S SW
Wind Speed: 6 8-10 9-14
Expected snowfall: 0 in. 0 in. 0 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.