Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Mon
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

Recent avalanches and continued stormy weather should be enough evidence to drive you toward conservative terrain on Sunday. Choose your travel routes wisely and keep an eye out for whumpfing collapses or shooting cracks as further evidence of instability. When in doubt, avoid slopes steeper than 35 degrees.

Preliminary Report: On Saturday morning, December 11th, an avalanche fatality occurred in the Silver Basin area of Crystal Mountain Ski Resort. See the forecast discussion below for additional details.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    Continued snow and wind on Sunday will thicken slabs throughout the West South zone. The potential for Storm Slab avalanches will increase as you ascend in elevation or on wind-loaded slopes. Slabs could involve newly fallen snow or break several feet deep into the storm and wind-loaded snow from the past week. Be sure to take the time to dig and check for strong snow over weak snow, storm density changes, and bonding to the old snow surface as points of failure before you commit to terrain. You can use test slopes as you travel to see how the recent snow is reacting to your weight to add context to what you are seeing in your pits. If your tests indicate unstable snow, you notice evidence of wind-loading, or you see recent avalanches, keep off slopes steeper than 35 degrees.

    (12/11/2021)

    Multiple avalanches were observed in the Crystal Mountain backcountry on 12/11. These slides occurred on multiple aspects and are a red-flag sign of instability.

Avalanche Discussion

Preliminary Report: On Saturday morning, December 11, a party of six backcountry tourers were traveling uphill in a closed section of the Crystal Mountain Ski Area known as Silver Basin. The party triggered a large avalanche on an N to E facing slope at approximately 6500’. While all members of the party were initially caught, four were partially or fully buried. A nearby party of two witnessed the event and immediately assisted in the rescue. Crystal Mountain Ski Patrol was also notified and responded to the scene. Unfortunately, one of the fully buried victims did not survive. NWAC and Crystal Mountain Ski Patrol will collaborate to conduct an investigation. Our deepest condolences to the family, friends, and community.

All areas in the West South zone have received notable precipitation since 12/8 as a parade of storms has dropped 2-4 feet of new snow, doubling the depth of our early season snowpack. The tragic incident near Crystal Mountain helps illustrate that although it is early season and snow depths are still building, many slopes have now reached the threshold where they can kill you.  Do not ignore the giant red-flag piece of information we just received. Avalanches are happening in our zone, and the storm is not done yet. As the storm parade continues, we should see the continued loading of slopes and the possibility of more avalanches. You need to be patient and give the snowpack time to adjust to its new load. The snowpack and season are both still young and there are plenty of unanswered questions about how the snowpack is shaping up. What we do know is that multiple feet of recent storm snow now sits atop a stout early-season crust that should be easily identifiable in your pits. All of the snow above this crust is in play for potential avalanches, so take the time to investigate for potential weak points and let us know what you see out there by submitting an observation.

"Uphill travel reminder: Check in with your local ski area this weekend regarding terrain access and parking updates. Closed ski areas often share a similar snowpack and avalanche hazard as the surrounding backcountry. You may also encounter other hazards like active avalanche mitigation, unmarked obstacles, snowmobiles, groomers, and other heavy equipment as ski areas prepare to open. Be prepared to make your own assessments and handle emergency situations.”

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