Vail & Summit County
AvalancheDylan Craaybeek · Jan 30, 2022 · Vail & Summit County
Snowpack
The height of snow on the slope varied from bare ground on the wind-scoured terrain above 12,000 feet to about 2 meters deep in the wind-loaded pocket where the rider entered the slope. The rider took about 3 turns before the avalanche erases the rest of their tracks on a convex rollover that had a slope angle of 38 degrees. The layer of failure was well-developed facets and depth hoar at the bottom of the snowpack. This weak layer was not continuous throughout the entire crown. The bed surface at the top of the avalanche hard (P to K on the hand hardness scale) faceted crust about 50 cm above the ground. This crust was only found in that one concave terrain feature on the slope. The avalanche stepped down to the ground within 100 feet of the uppermost portion of the crown. The slab was 1F to P- hard on the hand hardness scale and consisted of rounded grains that showed signs of faceting throughout the snowpack. The top of the snowpack consisted of wind broken precipitation particles, decomposing fragmented grains, and near-surface facets. Crown profiles were performed on portions of the slope where the crown was less deep than average due to overhead danger.
Avalanche
A rider triggered and escaped from a very large Persistent Slab avalanche on a northwest-facing slope, around 11,800'. The rider held onto a tree as the avalanche washed downslope through high-consequence terrain. This was a very large avalanche hard slab avalanche that ran just under 2000 feet downslope with a crown face 2 to 8 feet tall and a debris pile around 10 to 30 feet deep. The avalanche broke and carried dozens of small trees as well as a few large trees about 2 to 3 feet in diameter.