Observation: Public

Observation Details

Triggered Avalanches

Observed Avalanches

Signs of Unstable Snow

Observations

Traveling in the Blewett Pass Tronsen zone yesterday We did not observe any activity on our approach / climb even after checking on a few smaller test slopes. We arrived at our point of desired transition, there was another group here as well. They were investigating a small previously triggered slide. Looking up we noticed cornices and strong wind so it became apparent we are on the leeward side of this ridge and likely in a zone with wind loading. Within the next 30 minutes with very minimal movement our party along with the other group triggered and observed multiple shooting cracks, isolated moving slabs, and D1-D1.5 slides. One person in the other party triggered a very large shooting crack (100 feet) which triggered a sizable slab to break and run. All of these slabs were roughly 12-15” deep. All of this happening on extremely low angle slopes, by far the most reactive snow i have ever seen personally. Considering the Moderate Hazard Report for the day this activity was fairly surprising