Avalanche forecast

Northwest Mountains

Crested Butte Avalanche Center
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Avalanche danger

Sat
Alpine
4 · High
Treeline
4 · High
Below
4 · High
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Highlights

An Avalanche Warning is in effect through Saturday.  Heavy snowfall and windloading are overloading our unusually shallow and weak snowpack.  Large and dangerous avalanches are easy to trigger and will run naturally today. Travel in avalanche terrain is not recommended.  This avalanche terrain map can help you plan routes in simple, low-angle terrain without overhead hazards.  

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    2–3

    Exceptionally weak facets and collapsible crusts are widespread on the northern half of the compass and on some sunnier aspects at higher elevations below this week's snow.  As slabs thicken through the day, expect insta-weird behavior such as avalanches connecting across multiple terrain features, remote triggers, step downs or gougers into old layers near the ground, and variable feedback.  These issues are less common on most southerly aspects, and can be avoided on slope angles consistently less than about 30 degrees.   

    This avalanche ran yesterday near Marble, and is a good example of the widely propagating behavior we expect to see today as slabs thicken over buried weak layers.  

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1–2.5

    Heavy snowfall rates, increasing winds, and increasing snowfall densities are ideal ingredients for causing slab instabilities within the storm snow.  Storm slabs will grow larger and more dangerous throughout the day, and can initiate larger and wider avalanches that break deeper in the snowpack.  You can reliably avoid the problem on slope angles consistently less than 30 degrees. 

    Recent storm instabilities on Mt. Baldy

Avalanche Discussion

The small taste of natural activity over the last few days demonstrates how our poor little snowpack is responsive to relatively minor changes in the weather.  Now that we're in a major atmospheric river event, there's little doubt: an extensive natural cycle is underway.  Avalanches will break within the storm snow, in the facets and faceted crusts that formed during our terrible January dryspell (video from Cement Creek), and on older weak layers that formed at the beginning of the winter (video from Brush Creek).  The latter two comprise our persistent slab problem and will be the most destructive and difficult to manage - now and in days and weeks to come.  

Our last AR event just before Thanksgiving produced a number of amazingly wide, very large avalanches (D3), such as wall-to-wall avalanches in Red Lady Bowl, Mt. Axtell, and Redwell Basin.  With uncertainty on timing and location, we expect similar avalanches with this storm.  We're showing D3 potential today in the Northwest Mountains, where storm totals and existing snowpacks are larger, but we may also see a few in the larger terrain of the Southeast Mountains before the day is over.  Staying out of the runout zones is a prudent choice today. 

Upcoming Event - Open the storm floodgates with the Floodgate Operators at the Public House on Saturday, February 15. Tickets are available here.  Proceeds from the show to benefit the CBAC.

Regions covered