Avalanche forecast

Northwest Mountains

Crested Butte Avalanche Center
View on map

Avalanche danger

Mon
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
Open full map
Out of date — this forecast expired last year. You’re viewing past conditions, not the current bulletin.

Highlights

Dangerous avalanche conditions exist on some steep wind-loaded terrain. In these areas, avalanches could release in the recently wind-blown snow or step down to deeper weak layers while producing a destructive avalanche. Slab avalanches are comparatively less likely in wind-sheltered terrain and at lower elevations. You can further reduce your chance of triggering an avalanche through lower slope angle choices. The threat of wet loose avalanche activity will increase as temperatures climb above freezing and the sun further warms the snow surface. Consider moving to colder snow and out of steep terrain if you find a few inches of wet snow and/or see large roller balls in the terrain. 

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–3

    In the past week, we've observed large to very large slab avalanches breaking on weak layers in the upper snowpack and near the ground at higher elevations.  Feedback on the problem will be variable and infrequent. These issues are most concerning on wind-loaded terrain on colder, shadier aspects highlighted by the persistent slab rose.  Avoid steep, wind-loaded slopes, and wind-affected terrain with variable snow depths to reduce your risk.   Persistent slab instabilities are more isolated below treeline; stay alert on very steep or unusually shallow slopes. Southerly aspects typically lack the problem.  

  • Wind Slabs

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

    Over the last 24 hours, southwesterly winds at 12,000ft averaged in the 20's with gusts into the 40's and 50's on average. These winds fomred fresh wind slabs on the lee sides of terrain featuers. Carefully evaluate this instability below ridgelines and cross-loaded terrain features, or consider routing around that specific terrain. 

    An example of an old wind slab that was human triggered last weekend on Coneys. (3/15/2025)

  • Loose Wet

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

    The spring transition is back this week. As the sun warms the snow surface and temperatures climb above freezing, the threat of wet avalanche activity will increase. Wet loose avalanches will first develop on steep, sunny slopes that have rock outcrops radiating additional heat into the snow around them. Consider moving to colder snow and out of steep terrain if you find a few inches of wet snow and/or see large roller balls in the terrain. Where this avalanche problem overlaps near the persistent slab and wind slab avalanche problem, there is potential for a small wet avalanche to pull out a larger slab avalanche. 

    An example of wet avalanches that ran off the SE side of Cascade Mountain earler this winter. 

Avalanche Discussion

The trend to a lower danger rating was delayed as uncertainty around the persistent slab avalanche problem linger. In the last week, we have been plagued by a layer of small facets that was buried on March 13th. This persistent weak layer has produced a number of large human-triggered avalanches to D2.5 in size. While bigger triggers such as wind-loading and cornice falls have produced very large avalanches releasing deeper in the snowpack. Yesterday's snow and additional wind-loading are a bit too close in the rearview mirror to move away from the travel advice associated with CONSIDERABLE avalanche danger. 

A surprisingly large avalanche ran in the Climax Chutes yesterday. This avalanche took out about 80% of the start zone and covered around 70% of the avalanche path as it pushed into the flat valley below. However, what is more notable about this observation is the expansion of where the persistent slab avalanche problem is currently reactive. Last week, Schuylkill Ridge in the NW Mountains was the hot spot for this avalanche activity. While areas closer to Crested Butte and in the SE Mountain forcast area didn't have enough of a slab over this 3/13 interface to produce avalanche activity. Now, yesterday's snow has built onto that slab and potentially expanded where we will see avalanche activity on this interface. Where this interface has been buried deeply, those facets have gained notable strength, such as this observation highlights. However, where those facets have set around in a shallower snowpack, they remain weak and a potential concern. 

The snowpack moves back to the spring transition beginning today. Wet avalanche activity will begin today, before peaking on Tuesday and Wednesday. As we move into this warmup, it will become increasingly important to manage your timing for riding on steep sun exposed terrain and begin starting your days earlier so you can move out of that terrain before wet avalanche concerns develop. 

These links will take you to a more detailed summary of last weeks conditions. Text verson here, or video version here.

Events:  Stop by our next trailhead day this Sunday at Kebler TH.  We'll be grilling brats and celebrating the winter season!

Regions covered