Northern San Juan
AvalancheRyan Van Nuys · Jan 15, 2019 · Northern San Juan
Weather
Started under broken skies, becoming solidly overcast by mid afternoon. Temps in the mid 20's, light wind. at 10,500ft.
Snowpack
Generally supportive to a snowmobile once over 9,500 feet on west through north through east aspects, average snow depth in the 120cm range. Not supportive to humans weight once on foot. After noticing a few natural point release and small soft slab avalanches in near and above treeline areas with northern aspects, I investigated in a few representative pits. Found a reactive weakness about 20 cm down from the top, on a defined harder layer which appeared to be the failure layer in most slides I could see. There wasn't much slab development above this layer, but I was in a pretty protected drainage. Below this layer the midpack generally gained strength going from 4 finger hardness to 1 finger near the base... until the bottom 15 cm which were well developed, large grain facets. Also noticed a substantial amount of current surface hoar on near tree line terrain north through west facing slopes that will almost certainly be buried with the incoming snow.
Avalanche
Numerous small point releases, and small soft slabs near and above treeline on North, east and west facing terrain. Largest was estimated at 50 feet wide and 12" deep crown.