Steamboat & Flat Tops
AvalancheKreston Rohrig · Feb 10, 2019 · Steamboat & Flat Tops
Weather
Beautiful sunny day with light to moderate SW winds near ridge top.
Snowpack
For the most part the snowpack is deep with a very supportable and stout mid to upper pack. The height of the snowpack ranged from 150-200cm on the slopes we observed. On our uptrack we dug a quick pit on a NW slope around 10k feet and found a buried layer of surface hoar 30cm deep below the most recent storm snow. The SH crystals were only 3-4mm and were surprisingly well bonded to the layers above and below. ECTX on this layer, but failed easily on less formal shovel tilt tests. Up higher near ridgeline north and east facing slopes were heavily wind-loaded and corniced, making it impossible to get on slope for snowpack obs. I dug a second pit on a SW facing slope at 11200' near ridgeline and found a strong snowpack 195cm deep. There were a few layers of concern, with the most notable being a layer of buried near surface facets 40cm down. Similar to the surface haor on NW, this layer was not reactive (ECTX). See pit profile for more detail. We did observe a fresh D2 avalanche on a north slope that appeared to be intentionally triggered by a cornice drop. This avalanche looked to have cleaned out the most recently formed wind-slab, but also gouged into deeper layers further down the slope.
Avalanche
We observed the aftermath of a recently triggered avalanche from a large cornice drop that looked to be intentional. By the hole it left in the ridgeline, the cornice that hit the slope must have been the size of a Mini Cooper. Still, it gouged out the recent wind-slab and looked to have broken into some deeper layers further down the slope.