THIS AVALANCHE ADVISORY EXPIRED ON January 17, 2018 @ 4:43 am
Avalanche Advisory published on January 16, 2018 @ 4:43 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

The upper above tree-line elevations are still holding storm slabs from the last storm cycle.  Stability tests are showing that the snowpack is strengthening; but careful snowpack evaluation and cautious route finding are required in the high country. 

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

The upper above tree-line elevations are still holding storm slabs from the last storm cycle.  Stability tests are showing that the snowpack is strengthening; but careful snowpack evaluation and cautious route finding are required in the high country. 

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: Wet Slab
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Mountain weather forecasts are showing the potential for warm daytime temperatures. Watch for pinwheels; a red flag that the snowpack is heating up.

Avalanche Problem 2: Storm Slab
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Storm slabs have been showing results in stability tests, especially on the 1/8 - 1/9 rain crust, but bonding is improving very quickly.  Pay attention to new storm snow as it comes in on top of the melt/sun crust that has formed in the past couple of warm days. This could potentially be a future sliding surface, especially if surface hoar forms during cooler, clear nights.  

Avalanche Problem 3: Persistent Slab
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Stability tests have still been able to trigger on the Thanksgiving crust. This is getting harder and harder to find out there, especially on the N/NE aspects.  

recent observations

Thank you Gabe and the Silver Mountain Avy 1 class for giving thorough observations this week (see observation page). And also a big thanks to Miles, Brian, and Ty from Silver Mountain Ski Patrol for pit data (below).  IPAC greatly appreciates public observations, send them along!

 

 

 

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 likely Mostly Cloudy Mostly Cloudy then Slight chance of rain
Temperatures: 35 deg. F. 29 deg. F. 38 deg. F.
Wind Direction: E S NE
Wind Speed: 5-8 6 7-10
Expected snowfall: >.1in in. 0 in. 0 in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Chance of rain then rain/snow mostly cloudy Mostly Cloudy
Temperatures: 34 and dropping deg. F. 27 deg. F. 35 deg. F.
Wind Direction: SW SW S
Wind Speed: 11-13 8-13 13-18
Expected snowfall: >.5in 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.