Observation: Snake Creek

Observation Date
12/14/2015
Observer Name
Joey Dempster
Region
Salt Lake » Big Cottonwood Canyon » Brighton Perimeter » Snake Creek Pass
Location Name or Route
Snake Creek
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Speed
Calm
Weather Comments
Snowing lightly at 8pm, calm.
Snow Characteristics
New Snow Depth
12"
New Snow Density
Medium
Snow Surface Conditions
Powder
Red Flags
Red Flags
Poor Snowpack Structure
Red Flags Comments
Very well developed and weakly bonded facets under the new snow.
Avalanche Problem #1
Problem
Persistent Weak Layer
Snow Profile
Aspect
North
Elevation
8,300'
Slope Angle
30°
Comments

I skied up snake creek to the base of 8 ball tonight to have a look at the snowpack. I did not get to see a lot of snow, but what I saw was quite troubling. Total snow depth of 70cm. 30cm new with a weak crust from late Nov. underneath. Below the crust is complete crap, well developed facets to the ground. ECT produced Q2 shear (propagating all the way across, but not sliding energetically) at 11, although I have no doubt that if there was a bigger load on top the sensitivity would go to zero, especially as the crust continues to deteriorate.

As I did not sample a lot of snow, it is possible that I found the worst of the worst, but my guess is that it is very representative of the snowpack. I was near the bottom of the drainage, so the faceting could be more advanced due to colder air, but if I were traveling higher, I would consider the snowpack guilty until proven innocent.

The new snow is not forming a widespread slab, which is the only thing preventing widespread natural avalanches, but in any areas with relatively cohesive snow or wind slab, I would expect a human could trigger an avalanche easily with failure in the old snow.

Hazard is CONSIDERABLE in areas with preexisting faceted snow. I do not expect natural avalanches without signifcant new precipitation, but extremely weak underlying snow makes all steep slopes suspect and able to produce avalanches. On south facing slopes with no old snow, hazard is low. Skiing is poor on all aspects (not enough snow on S facing, able to punch through to rocks and trees in the 2 feet of snow on N facing).

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