Avalanche forecast

Northwest Mountains

Crested Butte Avalanche Center
View on map

Avalanche danger

Fri
Alpine
4 · High
Treeline
3 · Considerable
Below
3 · Considerable
Open full map
Out of date — this forecast expired 5 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Game on folks. Dangerous avalanche conditions have developed and will continue to become more dangerous over the next 24 hours. A natural avalanche cycle is expected to start off at upper elevations today and will expand to lower elevations tonight. If you are traveling in the mountains today, cautious route-finding and conservative decision-making are essential to avoid the most dangerous areas. 

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1–2

    The current storm is creating soft slabs that will be reactive to human triggering. This avalanche problem will first develop where these slabs are building over old weak snow. Those locations are generalized in the avalanche problem rose above. You can expect to trigger this avalanche problem on steep slopes where you find about 8" of new snow, over an old snow surface. This avalanche problem could also be remotely triggered from lower angled slopes connected to steeper terrain. 

    The avalanche size will be largest on wind-loaded slopes at near and above treeline elevations. In these same areas, a natural avalanche cycle is expected to begin this morning at above treeline elevations, before expanding to lower elevations this afternoon and overnight. 

    12/9 AM. Very small avalanches kickings things off on a northerly facing hill in Crested Butte.

Avalanche Discussion

I shouldn't have to tell you that we are in the middle of this winters first major winter storm. Looking out the window is a beautiful snowy sight. The avalanche danger is about to spike, so let's look at where the danger will increase first. The natural avalanche cycle is expected to begin first at above treeline elevations. This is thanks to the 12,000ft wind forecast gusting into the 50's from the west and plenty of snow available for transport. A natural avalanche cycle is expected to expand to all elevations overnight with the arrival of the peak precipitation rates. The timing of when a natural avalanche cycle will kick off at near treeline elevations is harder to call. Natural avalanches at this elevation will be possible today, before becoming more widespread later this afternoon and into tonight. The avalanche cycle below treeline will be the slowest to kick-off and even more specific. So let's get into some specifics...

We have had a very slow start to the winter and there was a lot of dry ground out there just a couple of days ago. Where there was dry ground, avalanche problems may not develop until tonight or tomorrow in the form of mid-storm instabilities. However, where there was snow on the ground a couple of days ago we can generalize it as "weak". If you spend some time in the observations tab you can gather more information on where that old snow is lingering and where it is weakest. 

Regions covered