Vail & Summit County
AvalancheAndrew McWilliams · Feb 21, 2024 · Vail & Summit County
Weather
Scattered clouds and moderate winds from the southwest. Temperatures warmed to near freezing.
Snowpack
I went to look at some recent avalanche activity near Uneva Peak on northeast and northwest-facing slopes at about 12,000 feet. The snowpack between these slides ranged from about a meter to nearly two meters in drifted areas. Where I dug on a northeast aspect the February snow was about 60cm thick resting on a soft layer of facets and rounding surface hoar. Below this weak layer is another nearly 90cm of snow - a dense slab resting on the basal facets and depth hoar. Both slides seemed to start in more recent snow, likely breaking at an interface formed around Valentine's Day. The slide on the east and northeast-facing slope broke more deeply into old snow near the ground. This particular path slid during an avalanche cycle during the mid-January storm (https://avalanche.state.co.us/observations/field-report/1c05be8b-d888-4327-a3ed-2be0e646889e). It's possible that the old snow near the ground and the weak layer formed after that storm cycle are the same in this path. It appeared that the slide was triggered by a large piece of cornice and it buried recent ski tracks. The weak layer buried around February 2nd is still my primary layer of concern here, an avalanche on this layer will likely be large and dangerous. We will need to see if avalanches breaking on the Valentine's layer keep happening after the storm cycle runs its course - while smaller, these avalanches are still dangerous.
Avalanche
The avalanches I was looking at were previously coded: https://avalanche.state.co.us/observations/field-report/269418c3-299a-4b42-b36a-2581624c9c72 https://avalanche.state.co.us/observations/field-report/33405fd8-048f-4cd8-ace3-6869e23ae551