Avalanche
- Slab Width
- 9 m
- Weak Layer
- New Snow
- Trigger Type
- Skier
- Vertical Fall
- 30 m
- Avalanche Type
- Soft Slab
- Slab Thickness
- 13 cm
- Trigger Detail
- Cornice Triggered
- Start Zone Aspect
- South
- Avalanche Problem
- Wind Slab
- Start Zone Elevation
- 3353 m
Our party was curious about the reactivity and size of wind slabs below the ridge line going to the summit of the Superior, so we intentionally dropped a very small, soft cornice by cutting it with a ski pole. When the cornice hit the top of the gully feature, it easily triggered a sensitive wind slab. (SS-ACS-R1-D1-S). The slab itself only ran for 30 or 40 feet, but then captured some loose snow, causing the entire avalanche to run for about 100 feet. There was certainly enough snow to knock a skier off their feet. Overall, the wind loading on the South Face was pretty limited and spatially variable. From our observation, wind loading problems in this area were limited to the slopes directly below the ridge lines, and wind loading was not occurring more than 50 or so feet from the top of the ridge.
The next photo is of another soft slab D1 avalanche which was intentionally triggered by a large rock we tossed onto occurred on a NE facing slope near Little Superior. It was mostly a loose sluff, but there was also some wind loading at the top of the path. This one ran for a couple hundred feet down into Cardiac Bowl.