Hard to piece last Sunday's avalanche together owing to poor visibility and a week's worth of snow and wind. One theory is that the party triggered the avalanche on a facet/crust layer that propagated 100' wide that sympathetic'd another one 400' wide further down the ridge. These two avalanches were 8-14" deep running on facets below a crust (possibly Jan 15/16).

The second avalanche stepped down to the facet/crust layering leftover from New Year's.

Analysis - see snowpilot - offered mixed results of ECTP14 on facets below the NYear's crust....and ECTX. CTs, oddly, failed on facets above the NY crust.

Photos:

Upper avalanche that had such wide propagation and sympathetic slide

Upper avalanche and step down avalanche (estimated 1' deep and 50' wide?)

Profile

Skinning toward the Sundial