Donaldson Peak - Lost River Range

My primary goal was to visit the site of the avalanche that claimed the life of a good friend and mountain brother. My secondary goal was to recover gear that remained at the accident site. I will provide a fuller accounting of the details of this avalanche when I have time in the coming days. Additional photos are attached to this observation.

Observations from tour on 5/11: An impressive cycle of solar and heat driven slab activity occurred in the lost rivers on 5/10. I observed these slabs on most aspects, generally at elevations above 9,500' or so. Slabs failed above the prominent crust that formed during warm temps and upper elevation rain at the end of April. Average slab depth of 30-45 cm (12-18"). There are faceted grains above this crust that developed during below average temperatures at the beginning of May. This layering is more thoroughly described in my two previous observations, and has been the main source of slab avalanche concerns since it was buried. This combination was the culprit weak layer in Friday's fatal avalanche. During my 5/11 visit, I initiated 4 sizable collapses on wind loaded slopes. Triggering slab avalanches that break widely remains a worrisome possibility.

Note: Avalanche Center staff edited the Observation Location and made minor edits in the Observation Summary.