Northern San Juan

Avalanche

Jeff Dobronyi · Dec 4, 2025 · Northern San Juan

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Weather

CLR skies, wind L gusting to M from the N, cold temps.

Snowpack

HS around 60cm at 10,900 and about 80cm at 12,300'. Where we travelled, there was a crust either at the ground in shallower HS areas, or crust over 20cm of facets at the ground in the deeper HS areas. The top 30-60cm was fist hardness. Throughout the day, a radiation recrystallization zipper crust formed about 2cm below the surface. We poked around the normal leeward features above treeline and couldn't find the continuous hard slab implicated in the recent larger avalanches, just fist hardness snow even in the most exposed areas. One collapse observed above treeline in a leeward feature. Settlement in HST on solar aspects observed throughout the day in the form of decreasing ski pen.

Avalanche

Soft slab triggered by ski cut on a planar E aspect at 1:30 pm.