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Observation: Grizzly Gulch

Observation Date
12/16/2020
Observer Name
Joey Manship
Region
Salt Lake » Little Cottonwood Canyon » Grizzly Gulch
Location Name or Route
Grizzly Area
Red Flags
Red Flags
Cracking
Poor Snowpack Structure
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
Underneath the recent snow is very weak faceted snow that has been collapsing. In some areas this snow has a crust on top and is not collapsing as readily. However, this could mean that it will just take a larger amount of weight to collapse it. As we keep adding more snow and the slab becomes more cohesive this will continue to be an issue.
Avalanche Problem #2
Problem
Wind Drifted Snow
Problem #2 Comments
Winds coming from the West have moved snow onto North and East aspects.
While I was there winds where calm and upper elevations where sitting in clouds.
Snow Profile
Aspect
West
Elevation
9,500'
Comments
Went for a little walk in the Grizzly area to see what some of the aspects where looking like. On my way up I found generally low density snow, some had a little bit of wind affect on top and I noticed a little warming due to greehousing. I got off of the skin track and immediatly noticed shooting cracks in multiple locations.
I did a full study put and noticed that the newer snow/old snow interface is sensitive and failing on the old snow that is faceted, ECTP11 @ 54cm, CT9 Q2 @ 53cm. This layer is of the biggest concern going foward.
Further down in the snowpack it is still faceted but seems to be a bit more consolidated. I noticed rounding at the very bottom of the back.
Bottom line is going forward this persistant weak layer will be reactive. Some areas with a crust on top of the facet layer may support more snow before they slide, which could lead to large, connected avalanches later this season.
On the bright side there are some very good turns to be had out there, but sharks still lurk below.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates