Aspen

Avalanche

Ben Pritchett · Nov 25, 2023 · Aspen

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Weather

Lightly snowy (S1), poor visibility, and almost no blowing snow. Gentle westerly winds barely moved snow on exposed ridgelines.

Snowpack

The unstable snowpack was in your face. Rampant rumbling collapses on the northwest and north-facing terrain we traveled in near and above treeline. Around 12 inches of snow fell overnight, with only 1 to 2 more inches during the day. The height of snow averaged around three to four feet (90-120cm), with snowmobiles and skis sinking around two feet. The storm snow had not settled, so the slab element was from the November 19-21 storm, with a fresh load of soft snow on top.

Avalanche

We triggered three avalanches. First we remotely triggered a large (D2) avalanche near 12,000 feet on a north-northwest-facing slope from around 600 feet away. This slide broke near the ground probably around 3 feet deep and ran between 600-700 vertical feet into the exit of the main bowl. Second, we remotely triggered a tiny pocket on a northwest-facing slope, several hundred feet away. It was the only steep feature nearby at that point. Third I triggered a small slope while skiing it on our second lap. This was the 4th track on the slope, each a little closer to a steeper part of the slope we were avoiding. We finally got close enough to it that it released. The slab broke 20 or 30 feet behind me and off to the side. It took several seconds to get moving. Once the cracks spread the slab over-ran 4 or 5 of my turns.