Northern San Juan

Avalanche

Jeff Davis · Dec 4, 2025 · Northern San Juan

View on map
Observation photo 1Observation photo 2Observation photo 3Observation photo 4Observation photo 5Observation photo 6

Weather

Calm, clear, cold.

Snowpack

Digging on the north and east slopes around 12,500 feet, the basal layers are not as reactive as I would have thought. The new snow is low-density, and with little wind, drifting was limited to just over the ridges. Snowpack tests highlighted a slab over a weak-layer setup at the new and old interface, but the new snow is slow to form a slab. There is a buried crust on many slopes that developed during the warm period around Thanksgiving and was not very reactive at the moment, but it is something to keep an eye on with the next load. I continue to find a burid 1-finger slab on some slopes, but its distribution is focused on open north-facing slopes. If you triggered an avalanche that breaks on this layer it would be large in size.

Avalanche

Widespread new snow avalanche activity on north-facing slopes.