Gunnison

Avalanche

Zach Guy · Dec 17, 2016 · Gunnison

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Weather

Pacific Northwest!! S2 most of the day with stronger pulses at times. Light winds below treeline, strong to extreme winds above treeline from NW and SW. Intense snow transport during gusts. Warm.

Snowpack

45cm of dense, new snow over well-documented PS structure, weak snow near the ground. Ski pen ~shin to knee deep. Lots of moderate collapsing, a few large collapses on various aspects. Widespread cracking on a density difference (stellar dendrites) mid storm, about 20 to 25 cm deep.

Avalanche

See photos and video. Very little margin for error in terrain selection today. Below treeline, we observed widespread natural storm slab avalanches and skier triggered a handful, all small in size. SS-N/ASc-R1-D1/1.5-S Near treeline, we observed two large natural persistent slabs, 2 to 3 feet deep, failing on facets near the ground. One on a NE aspect and one on a SE aspect. SS-N-R2-D2.5-O. We also remotely triggered 2 large persistent slab avalanches from ridgelines ~1-4 feet deep on the ground, one of which was triggered by a remote cornice fall. NE and N aspects near treeline. Debris ran far into flats and snapped numerous small trees. SS-ASr-R2-D2/2.5-O.