Northern San Juan

Avalanche

Chris Dickson Troy Nordquist · Dec 29, 2024 · Northern San Juan

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Weather

A warm sunny morning gave way to high cirrus clouds and breezy winds in the afternoon. Driving home we observed huge plumes of wind-blown snow coming off the peaks and ridgetops of the Sneffels Range, driven by a southwesterly wind.

Snowpack

We dug a pit on a northeast-facing slope at 10,300 and found a meter-deep snowpack. The snowpack was weak from top to bottom, with no layers harder than fist-hard. Despite that, we got easy to moderate failures in a compression test where new snow sits over faceted snow, but no propagation on these layers in a long column test. We did see natural cracking on many steep roadbanks.

Avalanche

We observed one small snowmobile-triggered Persistent Slab avalanche on a steep north-facing roadbank below treeline.