Vail & Summit County
AvalancheJason Konigsberg · Dec 7, 2023 · Vail & Summit County
Weather
Very windy in the morning with a lot of snow moving above near treeline on Bald Mountain. It's hard to say if the snow transport was effectively loading slopes. In the area I traveled, there were no obvious signs of instability related to recent drifting. Temperatures were mild but felt chilly with cloud cover and winds.
Snowpack
I dug on northeast, east, and southeast-facing slopes below and near treeline. A generalized structure is mentioned above in the summary. On east and southeast-facing below treeline, there is still not much snow. On southeast BTL, there are no basal weak layers. On east BTL, there is a transition zone at the upper end of this elevation band where faceted snow near the ground is more prominent. This is also true if you sway slightly to the north at lower elevations. In places where I found a thick slab over basal weak layers, I got easy to moderate propagating results in Extended Column Tests. Near-surface faceting on north through east was observed. On southerly slopes, there is a thick crust up to about 11,600 feet. Above this elevation, there was no crust on moderately angled (`~30 deg)southeast-facing slopes.
Avalanche
A large avalanche was observed near Peak 1 on a northeast-facing slope. I talked to a party that was in the area on December 5th and they did not notice the avalanche. It is possible they remotely triggered it on that day. It is also possible that it ran even more recently. The crown and debris look fresh. Also, numerous avalanches observed on northerly slopes near and below treeline. These avalanches most likely ran during the storm.