Not the current avalanche danger.
Archived in relation to a fatality on this day

Avalanche Forecast
Issued on:Sun, Jan 5, 2025 at 4:30 PM
Lat: 37.899, Long: -107.712
Tuesday, Jan 07

Above and Near Treeline: 3 - Considerable
Below Treeline: 2 - Moderate

New snow and strong winds increase your chances of triggering an avalanche in drifted snow near and above treeline. The most dangerous terrain is upper elevation slopes that face north, northeast, and east where dense, cohesive slabs of wind-stiffened snow sit on top of widespread weak layers. Here you could trigger an avalanche from a distance or from below and avalanches could break deeper and wider than expected. Avoid traveling near common trigger points, such as convex rollovers, rocky outcrops, or the thinner margins of a slab. Give yourself a wide buffer from suspect slopes steeper than about 35 degrees. 

Cracking and collapsing are signs of an unstable slope and an indication to move to lower-angle terrain. Be aware that you may not observe these signs of instability before triggering an avalanche.

Avalanche Problems

(1) Problem: Persistent Slab
Aspect/Elevation: W-N-E all elevations
Likelihood: Likely
Size: Small to Large

What you need to know about these avalanches

Persistent Slab avalanches can be triggered days to weeks after the last storm. They often propagate across and beyond terrain features that would otherwise confine Wind and Storm Slab avalanches. In some cases they can be triggered remotely, from low-angle terrain or adjacent slopes. Give yourself a wide safety buffer to address the uncertainty.

This information describes backcountry avalanche conditions within the area highlighted on the map. It is a regional forecast that describes conditions over a broad area. Local conditions may vary, even from one slope to another.

Southern Mountains Regional Discussion
Issued on:Sun, Jan 5, 2025 at 4:30 PM
Lat: 37.899, Long: -107.712

For how quickly it blew through, Saturday's storm packed quite a punch for the northwestern corner of the Southern Mountains. Gusty winds and periods of intense snowfall made for hazardous travel conditions, both in the mountains and on the roads. All said and done, storm totals met, and possibly exceeded, the upper end of the forecast with 8-10 inches of new snow in the favored areas of Red Mountain Pass, Telluride, the Uncompahgre Gorge, and the Cimarron Mountains. As you move south, snow totals decrease to around 2-4" on Molas and Coal Bank Pass, and around 2 inches or less for the remainder of the Southern Mountains. For the southern San Juan, La Garita, and Sangre de Cristo Mountains, no significant new snow means status quo conditions with no change to avalanche danger. 

In the areas that picked up the most snow out of Saturday's storm, backcountry travelers reported evidence of some minor natural avalanche activity above treeline and small skier-triggered Loose Dry and Persistent Slab avalanches below treeline. The strong south and westerly winds that came before the storm shifted to the northwest and north after the storm, transporting the low-density snow onto various aspects, resulting in small Loose Dry avalanches releasing out of steep terrain. All this new snow adds to the thickness of the slab that has been developing at the top of our snowpack since the holiday storms. This slab sits above a well-developed weak layer formed by our month-long December drought.

And just as we thought the likelihood of remote-triggering an avalanche was decreasing, a group of skiers remotely triggered an avalanche near treeline on Red Mountain 3 on Friday, January 3rd. This slide serves as an important data point in our understanding of the current Persistent Slab problem, and a CAIC forecaster investigated the crown of this avalanche on Saturday. The party triggered the avalanche while they were ascending low-angle terrain on the flanks of an open slope. It failed several hundred feet above them where recent winds formed a pencil-hard slab over weak facets. The group likely impacted the thinner margins of the slab, causing a collapse to travel through the weak layer and up into steeper terrain where the avalanche released. We shouldn't let our guard down with our current persistent slab problem. As someone wise once said, never trust a facet, or a hard slab, and especially not a hard slab over facets. 

The current Persistent Slab avalanche problem demands respect and patience. Continue to make conservative terrain choices and give steep connected slopes a wide berth, especially above treeline. Another storm arrives on Tuesday, and this time, it will bring fresh snow to most of the Southern Mountains.