Northern San Juan
AvalancheColin Mitchell · Feb 16, 2024 · Northern San Juan
Weather
Overcast and cool in the morning with a few flurries. Skies cleared midday making for a pleasant afternoon. Winds were light and variable with some minor transport observed in the higher terrain.
Snowpack
3" of new snow overnight landed on stout, mostly supportable crusts on south and west aspects, and on a consolidating slab elsewhere. The snowpack is gaining strength and upper and mid-pack layers are becoming more homogenous. Average HS in wind-sheltered, below-treeline terrain on the top of the pass was around 150 cm. There are two distinct slabs in the upper meter of the snowpack, separated by a crust/facet layer formed during the late-January dry spell. These slabs sit on top of a 50 cm-thick layer of rounding facets at the base of the snowpack. The basal facets are now insulated by the stiff slabs in the upper snowpack, and the main layer of concern is the mid-pack facets. Snowpack tests were unremarkable, one compression test produced a Q3 shear on the mid-pack facets, Extended Column tests did not produce a failure. Both facet layers are showing signs of rounding and gaining strength at this location. Areas with a thinner snowpack have been slower to strengthen.
Avalanche
No new activity observed