Southern San Juan

Avalanche

Jeff Davis Chris Bilbrey · Feb 20, 2024 · Southern San Juan

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Weather

Overcast with light to moderate southwest wind.

Snowpack

Digging on a northeast-facing slope around 11,800 feet, height of snow was around 175 cm. We found dry snow on the surface above a meter plus right-side-up slab. Hardness profile of the slab was 4F hard layers near the surface, trending to Pencil hard mid-pack, then 65 cm of 4F facets at the bottom of the snowpack. Basal facets appear to be rounding, and the "hand-squeeze" test produced small clusters. The only notable snowpack test results were hard, broken failures in Compression Tests (CTs). Multiple tests failed with 30 taps breaking at the top of the January facet layer. All in all, the snowpack in this area is deep, homogenous, and much stronger than many other places in the San Juan Mountains we've observed.

Avalanche

Evidence of a large avalanche that we best guessed ran during the February cycle - maybe around February 8. While most of the crown and bed surface had been filled in by recent snowfall and drifting, en echelon cracks were still visible above the crown and just below the ridgeline.