Vail & Summit County
AvalancheJason Konigsberg · Feb 5, 2019 · Vail & Summit County
Weather
Mostly sunny skies today with strong winds and warm temperatures. Snow was blowing around but it seemed like it was mostly sublimating and not loading slopes.
Snowpack
Below treeline the snowpack is completely faceted and barely supportable to skis. It would take significant slab building to cause any avalanche concerns.---Near treeline I dug 3 snowpits and received propagating results in 5 out of 6 tests. The most concerning was on south and southeast slopes where a small layers of facets failed on top of a melt freeze crust at 30 to 40 cm down from the surface. The relationship of the slab, weak layer, and bed surface was concerning as the fracture plane was smooth and planar with little resistance. Collapses were heard on southerly slopes today. This layer is likely responsible for much of the recent avalanche activity in the Vail and Summit zone. Although I also received propagating results on a north-facing slope at a similar depth, to me the crust facet combo which exists on southeast quarter slopes is more of a concern. Depth hoar near the ground is a future concern if we encounter a multi-day storm but the strength of the DH layer makes me think that basal layers are unlikely to collapse with small loads.
Avalanche
A few recent avalanches around the Montezuma area.The largest and most impressive was an east-facing slope off of Independence Mountain (backside of Keystone Resort). The avalanche was about 500 feet wide a looked to be several feet deep. I would speculate wind-drifted slab overloading facet/crust combo in upper snowpack.