UDOT PLANNED AVALANCHE CLOSURES!!

Observation: East Bowl

Observation Date
1/9/2020
Observer Name
Fink
Region
Salt Lake » Big Cottonwood Canyon » Silver Fork » East Bowl
Location Name or Route
East Bowl
Red Flags
Red Flags
Wind Loading
Poor Snowpack Structure
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Same
Problem #1 Comments
The storm outdid predictions and seems to have produced 8-10" of low density snow in upper LCC. Favored locations were deeper with 14-18" of fresh. I'm lumping new snow and wind drifted snow together as a single hazard for simplicity sake-- the new snow lacks cohesion and didn't form a storm slab in the S-SW-W areas where we traveled. Small, isolated, and sensitive wind drifts were encountered along the E-W ridgeline, and from a distance there was ample evidence of wind loading onto easterly aspects in upper silver fork. Long running sluffs were a possibility in steep terrain. Photo is of a sluff that ran from a little ski cut, 25' wide running probably 300-400 ft on top of the sun crust. An additional loose natural was noted on the E facing steep terrain near Doug's drop in upper silver. Winds were calm at ridgetops this morning, no additional snow transport was ongoing.
Avalanche Problem #2
Problem
Persistent Weak Layer
Trend
Increasing Danger
Problem #2 Comments
The crust-grauppel sandwich was present about 20 in down on SW slopes, easily identified in hand pits. There wasn't enough storm snow/overlying slab where I tested for it to be particularly reactive, but between the crusts loose grauppel remains without any bonding. Shovel shears were a bit stubborn, but still planar, failing at this weak layer. I expect increasing hazard on this layer as we get 1-3" of water in the coming days. Additionally, the new low density storm snow fell almost directly atop this crust in some locations, and the new snow could become the weak layer mid-storm if we see dense precip or winds.
Comments
Traveled from Alta to Michigan City and East bowl. Crust was present throughout but riding conditions were startlingly good. Aside from long-running sluffs, no instabilities were observed, just plenty of potential as noted above.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates