A bit of soft snow, mostly wind hammered surfaces and a triggered avalanche

CB Avalanche Center 2020-21 Observations

Date of Observation: 01/18/2021
Name: Zach Kinler
Zone: Northwest Mountains
Location: Anthracite Mesa
Aspect: East, South West, West, North West
Elevation: 9,400′-11,000

Avalanches: Observed the previously reported skier-triggered slide in the Purple Palace exit. HS-ASu-R1-D1.5-I

Weather: Lovely in sheltered terrain below treeline with temps around freezing, calm to light breezes. Light to moderate NW wind still pumping in open areas and closer to ridge line.

Snowpack: Mainly looking for soft snow in sheltered west-facing terrain on a quick rec tour. Previous travel in this area revealed HS in the 80-90 cm range before the recent wind event. Today HS was more like 60-70 cm with open areas being mostly scoured revealing past skin/ski tracks. Suttle terrain changes on these cross-loaded aspects created thin, small and very stiff(Pencil hardness) slabs. Avoided steep slopes involving terrain traps where these isolated slabs were found.

Visited the skier-triggered avalanche on the exit from Purple Palace on the way out. This terrain was a steep, East facing open slope where recent winds created a drifted pocket at the top the run. Once triggered, this small slide quickly accelerated downslope entraining mainly surface snow before stacking up deeply at the creek bottom below. Perfect example of how a small and isolated problem becomes magnified by the terrain.