Avalanche forecast

Northwest Mountains

Crested Butte Avalanche Center
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Avalanche danger

Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Up to 6" of new snow, combined with gusty westerly winds yesterday, formed shallow wind slabs in leeward terrain at higher elevations. Be cautious of fresh drifts in steep, consequential terrain, such as gullies or above rocks, cliffs, and trees. The avalanche danger will rise dramatically tomorrow and Wednesday as heavy snowfall overloads the snowpack.  

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Moderate to strong westerly winds drifted yesterday's new snow into shallow soft slabs below leeward ridges and in crossloaded terrain features.  The slabs formed over a variety of old surfaces and are expected to remain fairly sensitive to human triggers today.  Look for cracking or thicker, dense deposits of wind-blown snow to identify the problem.  You'll find safer riding where the new snow is softer and protected from the wind.  

    This is an example of a small Wind Slab avalanche from earlier this season. Similar avalanches can be human triggered today.

      Photo: Evan Ross

Avalanche Discussion

Sunday's storm system produced up to 6" in the Northwest Mountains and a few inches in the Southeast Mountains.  The new snow was accompanied by alpine winds blowing 20-30mph, gusting to 60 mph from the southwest to northwest.  This formed shallow wind slabs at higher elevations, favoring the east half of the compass.  With more transportable snow in the Northwest Mountains, wind slabs are expected to be a bit larger and more common west and north of town.  The problem should be fairly easy to recognize and avoid: look and feel for visual clues on the snow surface.  

Avalanche conditions will change significantly starting tomorrow.  Heavy snowfall on Tuesday will build slabs across all elevations, and as the storm progresses, natural avalanche activity will become more widespread and grow in size.  If snowfall forecasts verify, the avalanche danger will rise to High on Tuesday night.   Depending on how the storm system evolves, the snow favored Northwest Mountains might get there during daylight hours tomorrow afternoon. We'll hone in on the details tomorrow.  Our forecasters have documented the current weak snowpack (1,2,3, 4) over the past few days in preparation for this storm.  There are problematic facets and faceted crusts on most snow-covered slopes, especially those facing west, north, and east.  Stay tuned and plan to dial back terrain choices accordingly.

Regions covered