Vail & Summit County

The temperature was above freezing at the trailhead and in the 20s near treeline. Light winds from the west and northwest and broken skies.

Where we dug on an east-facing slope near treeline, the average snow depth was about a meter. The deepest drifted area we found was about 1.5 meters deep. The primary layer of concern here is a thin layer of near-surface facets below a recently formed wind-packed layer with about 20cm of the most recent snow on top. I got propagating failures here in Extended Column Tests and a failure to end in a Propagation Saw Test. An avalanche could step down to weak snow near the December 17 crust layer, too. While the snowpack was almost entirely composed of facets, it felt more supportable here than on similar slopes further east or south in the Front or Tenmile Ranges. The one somewhat recent avalanche we saw (one or two weeks old) likely failed on a similar layer on a south-facing, above-treeline slope. Where we dug on a northeast-facing near-treeline slope was a bit more sheltered than the east-facing slope. The height of the snow ranged from about 105 to 130cm. The uppermost 15 to 20cm of snow consisted mostly of smaller, wind-broken grains that were supportable to skis. As in the snowpit on the east-facing slope, the primary concern is the thin layer of faceted snow immediately beneath this slab, which formed between one of the recent periods of northerly winds and light snowfall. In one snowpit where this layer was buried 17cm from the surface, a Shovel Shear Test failed on this layer with minimum pressure, and an Extended Column Test fractured here with 12 taps but did not propagate. I found the rest of the snowpack in this pit to be comprised entirely of faceted snow of varying hardness.