Avalanche
- Slab Width
- 46 m
- Weak Layer
- Facets
- Trigger Type
- Skier
- Avalanche Type
- Soft Slab
- Slab Thickness
- 61 cm
- Start Zone Aspect
- Northwest
- Avalanche Problem
- Persistent Weak Layer
- Start Zone Elevation
- 2865 m
Cranky snowpack this year.
Gaining Porter Pass during gusty winds at 2pm I collapsed the slope and a crack shot out from my ski along the ridge triggering the avalanche. Two paths were triggered. The first in a small bowl beneath the pass, which is more of a test slope than a path. The second is the first Sox line west of the pass. Slope is about 20 degrees at the trigger point, but the Sox path is 40 degrees at the crown.
Crown was 150 feet wide and the slide ran 300 vertical feet. Failed on October snow, crown averaged 2 feet but was as much as 3 feet in spots. Snow was notably denser from wind effect near the pass at 9400 feet than lower in the drainage at 9100 feet. Crown was pencil hard slab. Debris pile averaged 1 foot but was as much as 3 feet near the toe.
Terrain is complex and had been skied by me on Tuesday and by another group on Wednesday, who I’ll call the Wednesday Crew (WC). WC demonstrated superb terrain management skills, at least as judged by my avalanche. Part of WC’s uptrack had disappeared under windblown snow and I didn’t realize the area had been skied until I had broken trail from 8600 feet to 8800 feet. I used WC’s skinner to get from 8800 feet to 9100, which, wisely, was their stopping point. About one-third of my skinner from WC’s stop to the pass was covered in debris.
First photo is the crack at 9400 feet gaining the pass.
Second photo is looking down from the pass at debris in the first path which did not hit my skinner.
Third photo is looking up the Sox path.
Fourth photo is standing at WC’s stop looking up the debris path. Part of my skinner not under debris is visible middle right in photo.