Southeast Mountains

The snowpack is on a slowly improving trend under a quiet weather pattern. Today's dusting of snow won't change that.   Skiers and riders around the state continue to get surprised by our challenging snowpack and tricky buried weak layers.    The most dangerous conditions are on leeward terrain features near and above treeline, where winds have formed larger and more cohesive slabs above weak snow. Today's avalanche problems can be remotely triggered and propagate wider than expected without giving clear warning signs.   Choose your terrain carefully.  

Yesterday, there were two large persistent slab avalanches triggered in Northern Colorado that required Search and Rescue response (Loveland Pass incident, Jones Pass Incident), and a skier near Park City, Utah was tragically killed in an avalanche.  While there are regional differences in how tender the snowpack is compared to Crested Butte, there is a common theme this year.  People around the West continue to get surprised by the unusually fragile weak layers that formed during our dry spells in November and early December.  With a lack of recent loading in the Crested Butte area, the danger has been at MODERATE for several days now.  Natural avalanche activity has ended and human triggered avalanches are possible.  The consequences of triggering an avalanche will be serious, especially near and above treeline where slabs are largest.   On the shaded half of the compass, the persistent slab problem is lurking on some, but not all,  terrain features. Identifying which slopes still harbor reactive persistent slab structures can be challenging:  subtle changes in slabs or weak layers can vary across terrain, making for inconsistent feedback from slope to slope with regards to stability tests or obvious signs of instability.   We are still receiving feedback that the snowpack is still sensitive to human triggers with daily occurrences of collapses and shooting cracks.    The simplest solution to handle uncertainty is conservative terrain choices.   You can easily avoid an encounter with today's persistent slabs by riding on lower angle slopes or on the sunniest aspects (south or southwest, and some southeast terrain).  Slopes that have previously avalanched have a safer snowpack structure.  Below treeline the danger is less pronounced because slabs are smaller and less common.  In the Southeast Mountains, we've trimmed the distribution of persistent slabs to highlight just the windloaded terrain near and above treeline.  In the Southeast Mountains, it is less likely to trigger a persistent slab in wind sheltered, below treeline terrain, particularly below 10,000 feet where the strong inversions have been decaying slabs.    In the Northwest Mountains, slabs are beefier and are more widespread below treeline.   

If you are stepping out into more aggressive terrain than in previous weeks, consider the potential size of each terrain piece and the consequences if it slides.  Slabs have the potential to connect across terrain features at higher elevations, making for larger and more dangerous avalanches.   Terrain traps such as trees and gullies can amplify the consequences at lower elevations where expected sizes are smaller.    Smaller terrain features with cleaner runouts offer lower risk options if you trigger an avalanche today.