Avalanche: Days Fork

HS-ASu-D2-O

Skier triggered hard slab on old snow 1-2 meters deep on a steep, convex rollover.

Forecaster Comments: On Thursday February 1 UAC forecasters went to look at this avalanche. The avalanche failed on a layer of weak dry facets near the ground. This avalanche was 7' at the deepest averaged 5' deep tapering off on the edges. This avalanche was on a steep 40 °+ slope (we measured 39°, 40°, 44°, 45°) in various locations on the bedsurface. This avalanche started in a steep rocky area skiers right of 2 dogs. This avalanche took out old tracks and ran well into the flats in Day's Fork. The debris had rocks the size of microwaves and other small appliances in the debris. What was interesting is that when the avalanche exited the steep rocky zone the stauch wall remained intact on the lower angle aprons below the steep piece of snow. See our observation HERE.

Photo 1- Location using Wasatch Backcountry Map

Photo 2- UAC forecaster Greg Gagne at the flank of the avalanche 4' (120cm) of pencil hard slab over fist hard facets

Photo 3- Looking up the debris towards the steepest and deepest part of the crown face

Photo 4- Snow profile adjacent to crown (skiers right side). Faceted dry weak layer is the same. Snowpit location did not have the 1F+ hard slab over weak dry facets