UDOT PLANNED AVALANCHE CLOSURES!!

Accident: Rocky Point

Observer Name
lees
Observation Date
Sunday, November 17, 2013
Avalanche Date
Sunday, November 17, 2013
Region
Salt Lake » Big Cottonwood Canyon » Rocky Point
Location Name or Route
Rocky Point
Elevation
10,400'
Aspect
Northeast
Trigger
Skier
Trigger: additional info
Unintentionally Triggered
Avalanche Type
Soft Slab
Avalanche Problem
Persistent Weak Layer
Weak Layer
Depth Hoar
Depth
2'
Width
150'
Caught
1
Carried
1
Accident and Rescue Summary

Our party of 4 choose to ski down the Rocky Point rib and slope to the right, one at a time. The 4th person triggered the slide as they made a cut across a slightly steeper rollover on the rib. They weren't able to get to the side, and then a ski came off. After riding the slide about 1/2 way down, were able to stop themselves mid track. Both poles and skis were recovered, one ski was up high (where released), the other gear was at the toe of the slide.

Terrain Summary

Complex terrain, where the snow didn't quite do as we thought. Planned on skiing either on the rib or in the lower angle slope to the right. Turns out that with current snowpack conditions, the steeper section at the top of rib was able to slide, even though the rest of the rib didn't. The slide was triggered at the steep break over at the top of the rib, and the portion that the skier was caught in was about 60' wide and 2 feet deep. However, the slide was able to propagate to skiers left, into part of an adjacent gully, where it was closer to 90 feet wide, and entrained much more snow. Much of the rest of rib didn't slide, so there were two separate debris piles.

Comments

Photo up at the crown - the slide averaged about 2" deep, with deepest section in adjacent gully perhaps up to 2 1/2 feet deep. The slide failed on the top of the depth hoar directly beneath the snirt (snow/dirt) layer. This was the main weak layer. However, interestingly, in portions, the slide stepped up to the near surface facet layer. The slide seemed to involve entrainment well down the track of the upper snowpack.

Comments

Looking up at the crown, viewers left side, where the slide was triggered.