Southern San Juan
AvalancheChris Bilbrey · Feb 15, 2022 · Southern San Juan
Weather
Lots of sun and a steady breeze along ridge tops.
Snowpack
Today's fortune is tomorrow's problem. Shady areas of slopes facing east and west, and northerly-facing terrain still hold soft riding conditions that consist of loose, cohesionless facets above harder snow layers or around faceted crust. We found around 8 inches of loose surface snow below treeline and up to a foot deep on wind-sheltered near treeline slopes. The weak snow surface will struggle to support a modest new snow load and sensitivity to rider-triggering is expected to increase once a slab forms above - especially if winds form stiffer slabs on the surface. As we approached treeline, we encountered more variability to snow surfaces. A thin wind skin capped weaker snow in broad, open areas that was adjacent to soft and textured snow surfaces. Loose dry sluffing near treeline was minimal on steeper slopes and on the backsides of convexities on northwest and north aspects where we traveled. More consistent wind-battering above treeline has left many areas scoured down to firm, old snow layers while forming stiff drifts above facets on northeast and east-facing slopes. We found a concerning wind-slab/ facet layer cake in the top 8 to 10 inches on an east-northeast aspect that failed twice while isolating the column to perform an Extended Column Test. This result is indicative of what could happen if a rider finds a spot where the wind-drifted layer above facets is thin making it more likely to impact weak snow below. Drifting on leeward slopes appears confined to near ridgetops, but triggering a small wind-drifted pocket has ample loose snow below to entrain while traveling down the slope making a more dangerous slide.
Avalanche
No recent avalanche activity. One large crown still visible on a north-facing slope of Peak N3 that most likely ran around the New Year. Slide failed at the base of steep cliffs and was several hundred feet wide.