Date of Observation: 12/31/2015
Aspect: North East, East
Elevation: 9,500’ to 10,800′
Weather: Clear, Calm and temps in the high single digits to low-teens all day.
Snowpack: Persistent slab over facets and depth hoar. HS ranged from 70-110cm throughout our tour. Ski pen was about 20cms and boot pen was still to the ground. We toured in terrain up to 36*, and got only a few isolated signs of instability (cracking and collapsing) but they were large and frightening. Lots of old avalanche activity on the lower NE side of Snodgrass in steep terrain, and surprisingly filled back in again, with HS in the old tracks back up to about 50-60cms. Avy problem on these slopes though was Loose Dry as opposed to Persistent Slab). Evidence that these paths ran early in the Xmas cycle. A profile on an old crown in steep terrain revealed a 120cm HS that was (top down) F>4F>1F>F>P>F and produced repeatable results of CTM Sudden Collapse on a thin crust (P) layer with facets (F) on either side of it close to the ground. Surface hoar was also observed 20cms below the surface but was unreactive.