Avalanche forecast

Northwest Mountains

Crested Butte Avalanche Center
View on map

Avalanche danger

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Out of date — this forecast expired 3 years ago.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

Highlights

Natural avalanche activity continued into Saturday, and it appears that a close call occurred with a large, human-triggered avalanche in Red Lady Bowl.  Avalanche conditions remain dangerous on Sunday as the snowpack slowly catches its breath from a multiday loading period.  Given the recent natural avalanches on wind drifted slopes, it's an easy choice to avoid leeward terrain features to reduce your risk of triggering an avalanche.  In sheltered areas, you can trigger avalanches in the recent storm snow, and on some slopes, avalanches might break about 3 feet deep on a layer of surface hoar.  Conservative slopes angles and cautious route finding will help reduce the chance of triggering a deadly avalanche.  You can reliably avoid triggering an avalanche by sticking to slopes less than about 30 degrees without steep slopes above.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–2

    Snowfall from late Wednesday through Saturday morning coupled with consistent moderate to strong westerly winds have created an avalanche problem in the recent snow.  Settled storm depths exceed a foot in many places in the Northwest Mountains and much deeper on drifted terrain.  Recently drifted terrain is the most problematic with the recent storm snow, but even sheltered areas could produce avalanches.  An avalanche in the storm snow could "step down" and release a much larger avalanche on weak layers lower in the snowpack.  Avoid wind loaded terrain, understand that you can release a deeper avalanche where the Storm Slab problem overlaps with the Persistent Slab problem, and make careful assessments of the recent storm snow on low elevation sunny slopes. 

    An example of a fresh natural avalanche failing in the recent storm snow.  Avalanches like his are possible today.

    (2/17/2024) Photo: Zach Guy

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–3

    A new round of weak layers was buried on February 2nd. These weak layers consist of widespread surface hoar and facets on most east, north, and west-facing slopes, and along with some faceted crusts on higher elevation southerly aspects. Slabs about 3 feet thick (even thicker on wind-drifted slopes) above these weak layers can be triggered by skiers and riders. This avalanche problem can be remotely triggered from flat terrain or may propagate further than expected.  Shooting cracks or collapses are a clear sign of danger, but these obvious signs of instability will not always show themselves before an avalanche releases.  There is isolated potential to trigger older, larger slabs on weak layers deeper in the snowpack, most likely from shallow terrain features or step-down avalanches.  

    You can reliably avoid trouble by selecting terrain with slope angles less than 30 degrees that are free from overhead steep terrain.

     

    This avalanche on Mount Baldy is a good representation of the broad and long-running potential of slides on drifted alpine terrain.  An avalanche like this would be hard to survive.

    (2/17/2024)

Avalanche Discussion

The recent storm only departed the area yesterday with snowfall ending early Saturday morning and wind-loading continued through the middle part of Saturday.  The snowpack is struggling to adjust to the new burden after multiple days of snow and west winds loading an untrustworthy snowpack.  Clear skies Saturday allowed observers to take in the scale of recent natural avalanche activity and it painted a clear picture of hazardous conditions on leeward terrain.  Take a look at our observations page to see the wreckage.  Please check out this observation from a presumed close call in Red Lady Bowl.  Although we are uncertain of the details of the Red Lady Bowl avalanche it appears to be human-triggered.

In both the Northwest and Southeast Mountains forecast zones, avoiding drifted terrain is a simple way to greatly reduce your risk of triggering an avalanche.  Dangerous natural avalanches ran in shallower parts of the forecast zone like Gothic Peak and Double Top and deeper areas like Mount Owen and Mount Baldy.  The most concerning aspects face northeast, east, southeast, and south.  Avalanche size on drifted terrain is deadly with the potential for some avalanches to be unsurvivable.  

Avalanche conditions vary in the sheltered terrain across the forecast zones.  In the Northwest Mountains where the snowpack is deeper, you can trigger avalanches in the recent storm snow and deeper on a layer of buried surface hoar/facets.  Observers reported natural avalanches on northerly and southerly aspects in sheltered terrain.  Skillful assessment is required to make good decisions about riding in avalanche terrain.  Avalanches in the storm snow may remain smaller, but if you release an avalanche 3 feet deep on the buried surface hoar it will become large.  You can simplify the conditions and complexity by choosing conservative slope angles.

In the Southeast Mountains, the snowpack has been showing more signs of instability and an increase in natural activity in sheltered terrain particularly on west through north through east aspects.  Observers noted frequent collapses on surface hoar around 1.5 feet deep (ob 1, ob 2) on Snodgrass and near valley bottom by Crested Butte.  The northerly and easterly aspects in sheltered terrain were screaming danger on Saturday.  Expect to trigger an avalanche if you enter steep terrain highlighted by the Persistent Slab rose.  Selecting lower-angled slopes is your best defense against triggering this likely avalanche problem.

 

Regions covered