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Observation Date
5/17/2015
Observer Name
Redd
Region
Salt Lake » Little Cottonwood Canyon » Alta Ski Area
Location Name or Route
Collins to Wildcat ridge
Weather
Sky
Obscured
Precipitation
Moderate Snowfall
Wind Direction
West
Wind Speed
Light
Weather Comments
Snow level around 8000 feet at 5am. Visibility was very poor, thick fog. Very slushy, 6" deep by 8500 feet, and slick as snot on the road. Snow was constant but got lighter and slowed to very light by 8am at 10,300 feet. Wind was light and from the West the whole morning. The snowfall was light and visibility was pea soup on the way back down, and I finally got out of the clouds and got good visibility around 9500 feet on the way down the hill.
Snow Characteristics
New Snow Depth
2'
New Snow Density
High
Snow Surface Conditions
Powder
Dense Loose
Wind Crust
Snow Characteristics Comments
Snowpit @ 10,250 feet, NE facing 39* slope, 7:45am, >270cm snowpack depth, 1.2m pit depth, 53cm of new snow comprised of 1-2mm broken stellar dendrites. ECTP-2 with a very low energy fracture 40cm deep, on top of a heavier layer in the new snow pack. After that failure, gentle prying on the column broke it at 55-60cm below surface, in the middle of the icy old snow surface layer, which was mixed forms 2-4mm 1F density. The bond between the new snow and the old snow was stronger than either one of those layers alone. Snowpack details: Air temp: -.5C Suface (0cm): Light/medium snow, difficult to pack into a snowball. -1.C -10cm: -2.C -20cm: -2.C -30cm: -1.5C -40cm: -1.C ECTP2-Q3 -45cm: F hard at surface to F+ here -45 to -48cm: 4F layer of new snow (must have been warm or wet when it fell) -48 to -53cm: F layer of new snow, well bonded to old snow surface underneath -50cm: -.5C -53 to -64cm: Mixed forms, 2-4mm, 1F, fairly well bonded -60cm: -.5C, after ECT test, gentle prying caused a failure across my block here, down to the bottom of this layer. -64 to -76cm: Rotten layer of mixed forms. 4F -76 to -82cm: P hard melt/freeze layer -82 to -120cm+: 4F 12" of new snow at Collins base 15-18" at 9000' 20-24" at 9300' -.5C air temp @ 6:30am 2' at 9800', -1C air temp @ 7am 2' at 10,250', -.5C air temp @7:45am
Red Flags
Red Flags
Heavy Snowfall
Wind Loading
Red Flags Comments
2" of dense, heavy snow at upper altitudes with some wind stripping and loading from the West. I was the first up Wildcat ridge, and stomped every cornus I could to see if anything reacted, but other than breaking off and falling a couple feet, the snow seemed to stay very well put.
Avalanche Problem #1
Problem
New Snow
Trend
Decreasing Danger
Problem #1 Comments
ECTP2-Q3 40cm deep in the ~60cm of new snow. On very steep slopes a big hard hit might be able to break it loose, but the new snow is so dense and it's compression strength is so high that it seems very unlikely to trigger anything, unless you stomp on a hanging shelf that isn't able to exploit the new snow's strength. If you did manage to break the weak layer in the new snow, it could possibly break down to the rotten snow underneath and escalate the severity.
Snow Profile
Aspect
Northeast
Elevation
10,300'
Slope Angle
39°
Today's Observed Danger Rating
Low
Tomorrows Estimated Danger Rating
Low