Observation: Grizzly Gulch

Observation Date
12/13/2024
Observer Name
Kelly, Kelly
Region
Salt Lake » Little Cottonwood Canyon » Grizzly Gulch
Location Name or Route
Bakers Dozen
Weather
Sky
Scattered
Wind Speed
Calm
Weather Comments
Scattered high clouds moving very quickly. Winds were calm at the 9,700' ridgelines and nearby weather stations at 11,000' were blowing from the southwest 9 gusting to 12 MPH. Air temp was around 15 °F.
Snow Characteristics
New Snow Depth
10"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments
Low density 4-5%. Settled snow depth was 7"-10". Nearby ski resorts reported 11.5"snow at .55" water and 9" snow at .45" water.
Above photo new snow with moon in the background.
Red Flags
Red Flags
Poor Snowpack Structure
Avalanche Problem #1
Problem
Persistent Weak Layer
Avalanche Problem #2
Problem
Wind Drifted Snow
Problem #2 Comments
Anywhere where the new snow is wind-drifted over the existing persistent weak layer will create a thicker, stiffer slab and be more of a concern.
Snow Profile
Aspect
North
Elevation
9,600'
Slope Angle
33°
Comments
In this area the new snow was still not enough to create a stiff slab over the buried persistent weak layer. The failures we saw were 8" (20cm) from the ground on weak dry faceted grains. The new snow in this location appeared to have bonded well to the old snow surface (but this won't be the case everywhere). If the new snow were to be wind drifted and create a stiffer slab then there will be more of an avalanche problem. I am still wary of any slope with buried facets and any area that is wind loaded will get lots of my attention. In this snowpit we had compression test results with failure on this weak faceted snow near the ground. I'll be looking for and avoiding slopes over 30° in steepness if I see signs of collapsing, cracking, and whumpfing.
We were able to initiate dry loose new snow sloughing in steeper terrain, but did not trigger any slides failing into the persistent weak layer in our travels.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate
Coordinates