Quick report
- Slope Angle
- 38°
Avalanche
- Slab Width
- 15 m
- Weak Layer
- New Snow/Old Snow Interface
- Trigger Type
- Skier
- Vertical Fall
- 183 m
- Avalanche Type
- Soft Slab
- Slab Thickness
- 20 cm
- Trigger Detail
- Cornice Triggered
- Start Zone Aspect
- North
- Avalanche Problem
- New Snow
- Start Zone Elevation
- 3109 m
We skinned up to the top off Jaws from Our Lady of the Snows in Alta. As we hit the ridge line we felt a couple small collapses (assumed to be wind slab). We skied into jaws from the east entrance coming in below the rocks. Across from us was a heavily loaded east facing slope, and the snow under our feet was sugary. We opted to sidestep out of the line.
We then dropped a refrigerator sized cornice from the top after checking to make sure that there was nobody below us. The cornice initiated a small wind slab with moderate propagation, this picked up speed and snow as it traveled down the slope and ripped most of the new wind affected snow out of the east facing wall.
Once the avalanche hit the apron, it broke 50-75ft wide, picked up speed, and ran through trees 5-10ft tall. After inspection it looks to have run on old recrystallized snow. The slab was made of wind affected heavy graupel and decomposing fragments.
After the avalanche ran, we felt good about no hangfire and we skied the slope. We probed the debris pile. It was 120cm deep in the deepest spot. As we skinned away we experienced localized collapsing and widespread cracking of the new snow slab on old recrystallized snow.