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Observation Date
11/17/2013
Observer Name
Greg Gagne
Region
Salt Lake » Little Cottonwood Canyon » Catherine's Pass
Location Name or Route
Catherine's Area
Weather
Sky
Broken
Wind Direction
Northwest
Wind Speed
Moderate
Weather Comments
-7 C @ trailhead at 0730. Some gusts along the ridgeline with partly cloudy skies. Bluebird when exiting at 1130.
Snow Characteristics
New Snow Depth
15"
New Snow Density
Medium
Snow Surface Conditions
Powder
Wind Crust
Snow Characteristics Comments

Widely-varied snow surface with some wind drifted areas well over a meter (3'+) deep, while on an adjacent slope there is less than 30 cms (12"). Overall the snow surface can best be described as "wind affected."

Red Flags
Red Flags
Poor Snowpack Structure
Red Flags Comments
Poor snowpack structure exists on steep, upper elevation northerly aspects. Still quite easy to find it although in some wind drifted areas the slab on top is 45- 90 cms (1.5' - 3') and mostly 4F hardness. On some of the off aspects (E/NE & W/SW I was finding a sun and temperature crust sitting above some faceted snow - though this is not that widespread an issue and I also don't think there was enough existing snow on these aspects to form a contiguous weak layer.
Comments

Early morning tour to Catherine's area and I was interested in seeing if the fresh wind deposits were sensitive, and how reactive the early October faceted layer is to the nearly 1 inch of water weight and drifting. Overall was finding the wind slabs were not reactive to any stability tests or ski cuts. The wind drifted snow can mostly be found on NE - SE aspects, although there was much cross loading as well. Drifts were found well down off of ridge lines as well. The early October faceted layer is easy to identify, and on a few quick pits I was unable to isolate a column 45 cm (1.5') in height that failed in the facets down near the ground. I did not get any collapsing on suspect northerly slopes, but my partner did get a localized collapse on a NE aspect.

I did get a view of the slide reported by Hardesty/Kobernik on the NE aspect near Rocky Point, but otherwise saw no natural or skier triggered activity. The feeling I came away with this morning was that the probability of triggering a slide on the faceted layer was generally Unlikely, but the consequences could be nasty. In addition, persistent weak layers are notoriously difficult to assess and manage, so even though I had few signs of a cranky snowpack (cracking, collapsing, etc) you have to focus on the poor snowpack structure. Judging by the number of travelers I saw heading in when we were exiting late morning, there will be plenty of slope testers this afternoon, and combined with any work done at the resorts, we should have a much better idea of the stability by the end of the day Sunday.