Northern San Juan

Avalanche

Julia Vorsteveld Jeff Davis · Dec 11, 2025 · Northern San Juan

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Weather

Very warm, sunny and light wind felt in the alpine.

Snowpack

Near and above treeline on northeast and east-facing slopes, areas of snow were firm from recent wind but drifted areas were broken up by small pockets of soft snow. In general the alpine in torched and wind texture was observed on many slopes. Snow was softer, faceted, and more forgiving below tree-line but still had an overlying stiff crust. Later in the day, the crust was breaking down, almost to a mashed potato-like texture due to rising temperatures. In a test pit, hard over weak snow was observed on a northeast-facing slope at an elevation of around 11,900 feet. There is a clear composition of wind-hardened snow composed of rounded grains, and then basal facets at the base of the snowpack. The wind stiffened snow was reactive in snowpit tests (ECTP10, ECP11, CTVE). The pit was dug in an isolated area of drifted snow.

Avalanche

Remnants of an old Wind Slab avalanche on north-east aspect near the top of Corkscrew Pass, near tree line. Wet Loose avalanche starting below steep, rocky southeast-facing terrain above tree line.