Vail & Summit County
SnowpackAndrew McWilliams Austin DiVesta · Jan 3, 2024 · Vail & Summit County
Weather
Below zero temperatures due to a valley inversion quickly warmed into the twenties with scattered clouds and light winds from the southwest.
Snowpack
The danger was LOW (Level 1 of 5) in this area, although we never made it above treeline. The northerly slopes that we could see above treeline did not have continuous snow coverage and had been heavily scoured due to the wind. Near treeline, we found a snowpack that was generally a meter or deeper, with a similar snowpack structure to many other areas in the Northern Mountains. In some areas what slab is left is getting weaker as this dry weather with warm days and cold nights continues. Nearly the entire snowpack is faceted, and there is not much slab left to transmit a failure. In other areas, there is still a dense, thick slab with unreactive snow near the ground and additional unreactive weak layers in the top one to two feet of the snowpack. In these areas, basal layers are not reactive in pit tests unless you give additional blows from the shoulder in addition to the initial ten. The upper weak layers displayed either no results or non-propagating results after taps from the elbow or blows from the shoulder. On a wind-loaded easterly slope, the deepest drift was about 200cm thick. In the middle of the path, the depth was closer to 130cm, and near the bottom of the path, the depth was about 100cm. We observed six recent avalanches just below the ridge in easterly that appeared to run on the interface of the new and old snow. With the number of tracks everywhere, I was unable to make a guess regarding how these avalanches were triggered and if any ran remotely or sympathetically. The surface snow was weak everywhere we traveled and surface hoar grains were widespread. In a shaded, sheltered area, we found surface hoar up to 3cm long that you could pick up between two fingers. With exceptionally weak snow surfaces and weak layers in the upper two feet of the snowpack, look for the danger to increase over the week as we add more weight to the snowpack.