Avalanche forecast

Northwest Mountains

Crested Butte Avalanche Center
View on map

Avalanche danger

Wed
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
Open full map
Out of date — this forecast expired 4 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Heightened avalanche conditions exist for the possibility of human triggering a large slab avalanche that breaks one to several feet deep on old weak snow, and for loose wet avalanche activity. The most recent and notable avalanche activity was reported last Sunday when a rider triggered a large slab avalanche on a steep slope below treeline. That observation is highlighted here and here. Today will be another beautiful day to get out in the backcountry, however, if you want to travel in avalanche terrain, current conditions will require you to carefully evaluate both the snow and terrain.

Avalanche problems

  • Persistent Slabs

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

    On northerly and east aspects, you can trigger a dangerous slab avalanche that breaks up to several feet thick on weak faceted snow that was buried last month. Slabs can be triggered remotely from below or adjacent slopes. Collapsing and cracking are clear signs of instability, although direct feedback on this problem has become less frequent. The most concerning areas are where previous wind loading has added additional stress to the snowpack. We have clear evidence of this problem from several destructive slides that ran last weekend You can reduce your risk by avoiding those wind-loaded areas and choosing slopes angles in the lower 30-degree range or less.

    3/12:  A large persistent slab that likely failed on Friday night from wind loading.  

  • Loose Wet

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

    High temperatures at 11,000ft are forecasted to push into the upper 30-degree range to near 40. As snow surfaces on southerly facing slopes become moist later today, human triggering loose wet avalanches will become possible. The potential avalanche size is mostly expected to remain small. However, at upper elevations, a triggered avalanche that starts small could be enough to pull out an old wind slab and produce a larger than expected avalanche. Use extra caution on steep rocky slopes where you find a moist snow surface, especially if you notice an old, thick-looking slab in the same terrain. This avalanche problem is expected to be less reactive at lower elevations that have already been cooked by the sun and yesterdays warm temps. 

    A skier was caught in this loose wet avalanche yesterday, near Aspen. 

Avalanche Discussion

The persistent slab avalanche problem remains in the spotlight, as the primary thing that could catch you off guard and potentially kill you. However it's not all doom and gloom out there, and there is some great riding to be had if you simply avoid the avalanche problem or chose slope angles in the lower 30-degree range and less. If you are choosing to ride in avalanche terrain, then you are either managing a level of risk acceptance or you are making detailed snowpack observations and informed decisions on whether the avalanche problem is present in the terrain you are riding. Past forecast discussions have highlighted the variability in snowpack structure on northerly and easterly facing terrain due to previous avalanche activity. Some slopes, for example, avalanched in late February and have yet to reform a new slab over the remaining weak layer. While right next door to those slopes you could find an intact snowpack that is a prime candidate for the persistent slab avalanche problem. Hints, the requirement for careful snowpack assessment if you want to make an educated decision about your avalanche terrain choices. 

On the wet avalanche front, many slopes started transitioning during yesterday's warm temps and clear sky. Today's focus for potential wet avalanche activity is on those upper elevations slopes that are still transitioning from dry to wet. Those are the areas where you may find the most recent snow becoming moist and possing a loose wet avalanche problem, or a stubborn old wind slab that reactivates during the peek of today's warming. Clouds are back in the forecast for tomorrow, so we can expect an end to any wet avalanche concerns, with persistent slab avalanche concerns remaining the primary avalanche problem. 

Regions covered