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Observation Date
12/23/2014
Observer Name
Kikkert
Region
Salt Lake » Big Cottonwood Canyon » Cardiff Fork » Georges Bowl
Location Name or Route
Cardiff Fork
Weather
Sky
Clear
Wind Direction
Northwest
Wind Speed
Calm
Weather Comments
One of those mornings...cold and clear post storm. Winds calm.
Snow Characteristics
Snow Characteristics Comments

The windy portion of the storm created a nice dense supportable layer above 8,500', with total snow depths above 8,500' of up to 2 feet. Below 8,500', there was a rain crust of varying thickness, capped by about 5 inches of new from the tail end of the storm. At upper elevations, the density inversion has settled out, and as mentioned above was supportable, with ski penetration within the top 6-8" only. The top 6-8" was a mix of rimed particles, with a bit of cold fluff from overnight on top. Easy travel, nice conditions.

Red Flags
Red Flags
Heavy Snowfall
Wind Loading
Collapsing
Poor Snowpack Structure
Red Flags Comments
Because the new snow is so supportable, we only got a few collapses. However, the real obvious clue is that we just dropped over 2 inches of water with some of the strongest winds I have experienced onto a snowpack that had weak snow present prior to the storm. That's the forest, no need to focus too much on the trees, and we chose lower angle terrain. Also, hoped to see some good crowns in mineral, mill b, or broads, but seemed like things probably blew back in right after running and nothing was super obvious (could see a bit of debris in Bonkers, but no obvious crowns and could have been a small glide).
Avalanche Problem #1
Problem
New Snow
Problem #1 Comments

There is so much variability out there in terms of how much new snow is where, as well as what areas had weak snow prior to the storm. That has good and bad I suppose. The good being that persistent slabs may only be pockety (a theory I really am not really willing to test...see above regarding terrain choice), the bad being its difficult to assess stability (snowpits and test results vary widely). That said, in pits where I did have buried facets from early December, there were nice clean shears and full propagation with moderate effort (ECTP 17). Will be nice to see how things react to the next load and then reassess from there.

Snow Profile
Aspect
Northeast
Elevation
9,500'
Comments

Wanted to see how variable things were, so dug several pits. From what I saw, buried facets from early December seem present in more protected areas, less present near ridgelines where they may have been scoured out. But, lots of variability, so take it for what it is worth. Clean shears and nice propagation where there were buried near surface facets. Below 8,500 feet, snow was thin and weak, but there was not load.

Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates