Gunnison

Avalanche

Ben Pritchett · Mar 5, 2019 · Gunnison

Weather

Light westerly winds brought increasing clouds throughout the day. Overcast by mid-afternoon. High temps in mid 20's at 11,000', with above freezing temps in the valley floor.

Snowpack

This observation is from a very deep snowpack, with an average height of snow >200cm, with numerous areas over 300cm with only light signs of drifting. The storm interface (down 60cm) below the March slab is still identifiable, but not propagating in our snowpack tests. Down ~100cm, we found crusts with a layer of rounding facets above and below, but they are buried deeply and would require a large trigger to break. We experienced one booming collapse in an area with around 150cm of total snowpack depth. At this location we also observed ECTP 13 result down 65cm on large grained fist-hard facets. The huge overburden on the weak layers in shallow areas is spooky, but the deeper areas are showing signs of gaining strength rapidly after the early March storm.

Avalanche

In the Ruby Range, most avalanches released at the March 1st interface, down about 3-4' deep. Some only broke this deep, but many broke into old faceted layers below growing much larger in volume and breadth.