Avalanche: Rocky Point

Observer Name
UAC Staff/Anonymous
Observation Date
Sunday, November 19, 2023
Avalanche Date
Sunday, November 19, 2023
Salt Lake » Little Cottonwood Canyon » Albion Basin » Rocky Point
Location Name or Route
Rocky Point
Avalanche Type
Soft Slab
Avalanche Problem
Wind Drifted Snow
Weak Layer
New Snow/Old Snow Interface
Saw a group drop a similar aspect and decided to push up one more drainage. We jumped on the slope from the top. Ski cut the top with no reaction before riding. Rider went saw wind slab triggered and immediately exited with speed to established safe exit that was talked about before in case anything went. It was almost a delay but stepped down into the PWL. This part connected to the ridge on the right and across into the secondary gully about 200 yards across and I'd say 18-20 inches deep.
Forecaster Comments: Members of the Utah Avalanche Center staff went to look at this avalanche on November 20, 2023 ( one day after it was triggered). It appeared to have failed 9-11” off the ground on some very weak faceted snow above a crust. Extended Column Tests above the fracture were ECTP1 and ECTP3 @23cm from the ground. Which means that the tests had very easy propagation across the weak layer with 1 and 3 taps from the wrist. The avalanche itself was on a steeper wind loaded area 1/4 of the way down the slope. What was interesting is that it pulled into the rocks on lookers right and the slope really needed the connected wind drift and the steepness as well as the additional weight of the rider to be triggered.
The below photo shows 6mm depth hoar with striations that was 4-6" off the ground and mixed in between the crusts. This layer of weak snow forms when there is a strong temperature gradient which often happens in early season when the snowpack is thinner and more shallow. These layers which have been found on shady aspects are worth paying attention to with each snowstorm and are suspect layers where avalanches may be triggered until proven otherwise.