Avalanche forecast

Northwest Mountains

Crested Butte Avalanche Center
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Avalanche danger

Sat
Alpine
1 · Low
Treeline
1 · Low
Below
1 · Low
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Out of date — this forecast expired 8 months ago. You’re viewing past conditions, not the current bulletin.

Highlights

Slab avalanche problems are isolated and increasingly difficult to trigger. The main concern remains previously wind-drifted upper-elevation slopes, where stiff slabs overlie early-season weak layers. If you encounter this poor structure, consider shifting to lower-consequence terrain to reduce the risk of an unlucky outcome or steer around old drifts. Wednesday night’s windstorm may have also created small, fresh slabs in unusual or lower-elevation locations.  Simply steer around these fresh, hard drifts to manage the problem.

Avalanche problems

  • Persistent Slabs

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

    Snowfall and wind drifting in early December formed slabs up to a few feet thick over facets near the ground.  These weak layers are most widespread on the northern half of the compass.  Though the snowpack is adjusting under mild weather, the threat lingers on some slopes with well-developed slabs, most commonly at mid- to upper elevations and on leeward slopes.  Carefully assess the snowpack structure and consider terrain consequences before riding in steep terrain on problematic aspects.  Default to lower slope angles or travel on terrain that was bare ground through November when in doubt.

    A skier triggered persistent slab avalanche on Sunday, 12/14.  

    East aspect of Cinnamon Mountain. 

Avalanche Discussion

The last significant loading event and associated natural avalanche cycle occurred around the weekend of December 6, followed by a few periods of additional wind loading. Over the past week and a half, the likelihood of human-triggered avalanches has steadily decreased to unlikely. Remaining areas of concern are isolated and primarily found on previously wind-loaded upper-elevation slopes.  Recent snowpack tests have shown variable results but generally indicate a low likelihood of triggering. The most recent human-triggered avalanche occurred on Sunday, December 14, on an easterly-facing slope on Cinnamon Mountain. While avalanches like this have become increasingly rare, they are not impossible. Carefully consider the consequences of triggering a strong-over-weak snowpack, and reduce your risk by avoiding drifted slopes with terrain traps.  You can avoid this problem by choosing lower-elevation sheltered terrain.

Wednesday night’s extreme wind event created a minor concern, with small, sensitive drifts forming in unusual locations due to the powerful winds. Limited snow was available for transport, consisting mainly of about an inch of new snow and older facets in wind-sheltered terrain on the northern half of the compass.  Explosive control work was able to pry one of these small slabs out on Thursday.  Much of the soft snow before the wind event was found below treeline, so don't be surprised if you find a small slab at lower elevations.

Upcoming Events:

  • Fireside Chat: Join us at the Daily Dose on Friday December 19th 5-7 pm to hear Matt Steen discuss professional decision making in avalanche terrain. Helicopter Skiing Lead guide manages avalanche terrain in the San Juan Mountains of Colorado. Come hear his interesting perspective.
  • Trailhead Day: We will also be at the Washington Gulch trailhead for our first Trailhead Day this Saturday from 10 a.m. to 3 p.m.

Programs like the Fireside Chat Series and Trailhead Days are made possible through funding from MetRec, STOR, and the National Forest Foundation

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