Gunnison
SnowpackZach Guy · Jan 22, 2012 · Gunnison
Weather
Temperatures were in the mid teens at the lower study plot to single digits on ridgetop. Winds were generally moderate from the west, gusting to 40 mph. Light to moderate snowfall continued through the day, with accumulations of 4" since 8 a.m.
Snowpack
Snowpack Structure: H2D Snowfall totals as of 4:00 p.m. are 25" with the storm board showing 19" (2.25" water). Below treeline on west slopes, this storm snow rests above approximately a foot of denser windslab which formed earlier this week (with a 2mm layer of rime crust above it on many slopes). Below this slab (~2-3 feet), the snowpack is either completely faceted or faceted with numerous crusts. These basal layers have been reactive in the past week, and were touchy today with the larger load, failing naturally or easily under ski cuts. Above treeline, wind erosion and loading has created a more variable snowpack, which we did not observe directly today. Avalanches: On the steep west terrain, we observed roughly ten soft slab avalanches today, both natural and skier triggered. These all failed on a thick layer of facets near ground, with slab depths between two and three feet. The slab sizes ranged between R1D1 to R2D2. Most of avalanches occurred on steep rollovers or below cliff bands, especially in lower portions of the terrain where packing and explosive efforts were not concentrated earlier in the season. I've heard guides say several times this week "Whoa, we've never seen that slide before." Snowpack is touchy with the potential of avalanches occurring in unexpected pockets. We also experienced fairly widespread whumphing on west through south aspects.