Avalanche forecast

Northwest Mountains

Crested Butte Avalanche Center
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Avalanche danger

Thu
Alpine
2 · Moderate
Treeline
2 · Moderate
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Out of date — this forecast expired 8 months ago.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

Skier and remote-triggered avalanches early this week (Marble 1 and 2, Schuylkill Ridge, Pearl Mtn) show that 1 to 2-foot slabs are possible near and above treeline, failing on faceted weak layers. Watch for cracking and collapsing, dig down a couple of feet to assess the structure, and use visual clues to identify slopes with recent slab formation. Carefully weigh terrain consequences before committing to steep slopes where slabs exist. The safest travel is below treeline or on wind-eroded terrain.

Avalanche problems

  • Persistent Slabs

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

    Soft slabs of recent and wind-drifted snow are sensitive to human triggers where they formed over thin crusts and faceted weak layers,  typically near and above treeline.  Buried weak layers are most widespread and well-developed on the north half of the compass above ~10,700', but have also been found above buried crusts on southerly aspects.  Underneath last week's storm snow, the old snowpack is highly variable due to droughts, record-warm temperatures, and previous extreme wind events. Expect variable feedback as you change aspect and elevation, or move from one part of a slope to another.  Slopes with the slab + facet ingredients can be remotely triggered or propagate wider than expected.  This video illustrates the problem.  

    (12/28/2025)

    The crown of a skier triggered persistent slab on Schuylkill Ridge.  The slab consisted of about 18" of recent snow over weak facets near the ground, and propagated about 350' wide.    

Avalanche Discussion

Avalanche danger continues a gradual downward trend as the snowpack adjusts to last weekend’s loading. Recent avalanche observations point to leeward aspects—generally northeast through southeast—near and above treeline as the most concerning areas to find lingering instabilities. Due to Sunday's modest snowfall amounts and strong winds, slabs remain relatively thin and are often discontinuous or confined to leeward features.  A few slabs in the Northwest Mountains connected across broader start zones, and some slabs released in wind-protected terrain near treeline.  This behavior is likely decreasing now that we've had a few clear nights for those very soft slabs to decay.  The problem is becoming increasingly localized but still capable of producing human-triggered avalanches in the right place.  This downtrend should reverse with expected snowfall on Thursday and Friday.  

The main threat of triggering an avalanche is tied to faceted snow that formed during the December drought and was preserved on select slopes - most commonly colder aspects above the Christmas rain line (~10,700) and sheltered from the extreme northwest wind event. Where recent snowfall and wind loading have created a cohesive slab over those facets, avalanches can still be triggered in steep terrain. On the south side of the compass, additional uncertainty exists where small-grained facets above a thick sun crust were buried last weekend, though their distribution and sensitivity are less clear. With variability in weak layer characteristics, focusing on the presence or absence of a cohesive slab, and weighing terrain consequences if it fails, remains an effective strategy. 

Regions covered