Southern San Juan

Avalanche

Chris Bilbrey · Dec 9, 2021 · Southern San Juan

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Weather

Obscured skies and light snowfall for most of the morning. Snowfall intensity picked up around 12:30 pm and was a solid S2 by 2:30.

Snowpack

We did not have to look hard for evidence of unstable snow. This was confined to northerly-facing slopes above 11,000 feet. Dense storm snow is quickly stressing buried weak snow. We observed numerous collapses and long-running cracks failing in F hard facets (1 to 3 mm). ECTs confirmed similar, touchy conditions, with propagating failures on 11 taps. We found drifting on the lee sides of terrain features 1 to 2 feet thick. Southerly-facing slopes without old, faceted snow were still thin, but offer reduced risk to avalanches.

Avalanche

No fresh natural avalanche activity. However, we observed lots of natural slope wide cracks near treeline where slope angles exceeded 32 degrees. We were able to initiate a second round of en-echelon cracks and long-running cracks on those same slopes. In one instance, we were around 150 feet away from the slope.