Northern San Juan
AvalancheChris Dickson · Dec 7, 2025 · Northern San Juan
Weather
Temperatures started off cold in the morning, gradually warming to the mid to upper 30s by noon. Sunny slopes began to warm and moisten in the afternoon. Snow surfaces remained cold and dry in shaded areas. Winds were calm with occasional light gusts coming from the southwest.
Snowpack
Since November 30th, we've basically doubled the snowpack in this area, adding 2 inches of snow water equivalent. That said, we're still below average and shallow. The snowpack deepens with elevation, increasing from 40 centimeters to around a meter in deeper spots at upper elevations. Near and below treeline, in sheltered areas, the snowpack is mostly unconsolidated and faceting, lacking a slab. On more open, exposed slopes, the recent winds formed thin windskins, and above treeline, this thickened into a 10cm surface wind slab. In a pit dug at 11,800' on a northeast-facing slope, I found around 85 centimeters of snow, with a layer per storm. Notably, there was a well-preserved layer of buried surface hoar buried about 45 centimeters down, which likely formed during the Thanksgiving week dryspell. It did not propagate in tests.
Avalanche
Large natural avalanche on Pilot Knob, northeast slope above treeline. Otherwise, limited cycle of small Wind Slab avalanches below ridgelines, mostly on leeward slopes.