Aspen

Avalanche

Brandon Levy, Dylan Craaybeek · Dec 19, 2022 · Aspen

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Weather

There was the usual valley inversion in place this morning driving up to the road summit of McClure Pass. Three degrees farenheit at the CR3 turn to Marble and 15F at the road summit around 0800. The sky cover was clear throughout the morning and the wind was generally calm.

Snowpack

We triggered several terrain feature scale collapses while traveling on the easterly-facing slopes above SH133 on McClure Pass. There were only visible cracks associated with the collapses on a short slope around 30 degrees and the collapses became smaller but more numerous as we descended to the road elevation from 9600' to 8500'. We dug two snow profiles. One was after we triggered a collapse above the Lone Tree Bowl start zone at 9600' and the second was located at 9100' and more representative of the lower elevation paths above SH133. Both profiles revealed the poor snowpack structure with the mid-November drought layer down approx. 55cms. This layer was the failure layer for long and small column tests--see profiles for more info. The snowpack surface is weakening and composed of near-surface faceted grains up to 1 mm or surface hoar up to 6mm. The near surface faceted grains are about 10 to 15cms thick.

Avalanche

Several very small loose dry avalanches in the east-facing portion of the Lone Tree Bowl start zone.