Observation Date: 12/20/2014
Route/Location:
We skied east facing slopes above Heart and Hidden lakes in the Great Burn.
Weather:
Light snow and freezing rain. Winds to 10 mph, normal wind loading. Up to 8″ of dense snow on Stateline.
Wind:
New Snow: 6-12″
Avalanche Activity:
Other Comments:
We found isolated but very touchy buried surface hoar during our tour around Heart Lake yesterday. The surface hoar appeared to be limited to sheltered east facing terrain and where it existed we were able to easily remotely trigger slabs up to 10″ deep and 200′ long on slopes as low as 30 degrees from several hundred feet away. The surface snow profile was: 8″ soft wind slab, 2″ facets topped by thin buried surface hoar (from 12/13 storm), ice crust. In areas with more wind and sun exposure, the snow was more stable. The pockets of buried surface hoar presented surprising and dangerous avalanche conditions since the hair trigger spots were isolated, and the snow generally felt stable (i.e. no collapsing or natural avalanche activity).
We dug a quick pit on an east facing slope around 6,500 feet. The buried surface hoar did not show up in the pit, and we were getting failures at CT11Q2/ECTN 13 at 4″ (overnight snow) and CT15/Q1ECTN 15 at 8″ on the facet layer. Buried surface hoar was not present in the pit.
We were able to drive to Heart Lake trailhead with a 4×4 truck.
Observer: Brian Story