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Observation Date
12/11/2016
Observer Name
Paradis
Region
Salt Lake » Little Cottonwood Canyon » Grizzly Gulch
Location Name or Route
Grizzy Gluch
Weather
Sky
Scattered
Wind Direction
West
Wind Speed
Light
Weather Comments
Felt a lot more like winter after yesterday's wet weather. Day started overcast with clouds intersecting higher ridges then cleared a bit over the course of the day. Winds were relatively light.
Snow Characteristics
New Snow Depth
12"
Snow Surface Conditions
Powder
Snow Characteristics Comments

Snow was relatively stiff in wind exposed areas but skied well. Snow depth varied greatly due to wind, with some small gullies trapping deeper new snow.

Red Flags
Red Flags
Recent Avalanches
Wind Loading
Cracking
Poor Snowpack Structure
Red Flags Comments
Although instability was less obvious today than yesterday closer inspection of the snow showed two weak layers and some cracking in the new snow. The most significant weak layer was some near surface facets burried at the interface between old and new snow at about 60 cms deep. It was also possible to trigger small wind slabs that appeared to break on the grauple layer, although this will probably heal quickly.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments

As shown in photo below (with weak snow removed) the persistent weak layer under a significant slab was my greatest concern today. This seemed like a low to medium probability high consequence situation. We did not observe any collapsing on this layer although large collapses had been reported previously. Weak layer produced a clean shear in ECT test although did not pop out with a ton of energy.

Avalanche Problem #2
Problem
Wind Drifted Snow
Problem #2 Comments

Wind slabs were relatively easily triggered today and they appeared to be running on the layer of grauple from yesterday that was reported in LCC. These will probably stabilize a more over the next few days.

Cornices were also very sensitive.

Snow Profile
Aspect
South
Elevation
10,100'
Slope Angle
28°
Comments

Relatively easy results from ECT with clean shear was perhaps the most significant red flag of the day.

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