Observation Date
1/31/2015
Observer Name
Greg Gagne with Westminster College Level I Class
Region
Salt Lake » Little Cottonwood Canyon » Grizzly Gulch
Location Name or Route
Grizzly - Twin Lakes
Weather
Sky
Clear
Wind Direction
East
Wind Speed
Calm
Weather Comments
Temps were reasonable in the shade, not so in the sun. Perhaps a hint of easterly winds along Twin Lakes Pass ridgeline.
Snow Characteristics
New Snow Depth
1"
New Snow Density
Medium
Snow Surface Conditions
Powder
Dense Loose
Faceted Loose
Wind Crust
Melt-Freeze Crust
Damp
Snow Characteristics Comments

In most years I'm not even sure we'd notice a few cms of new snow, but it's a pretty big event this season and in fact made for nice riding and travel conditions today.

Comments

Toured with a group of Westminster college students today in a Level 1 class. This observation is a summary of what we found:

- Overall Low danger with a solid supportable snowpack to the ground.

- Upper LCC is still (somehow) holding onto snowpack depths of a meter on shady aspects. The snowpack is supportable and quickly goes from 4F to 1F

- We were able to find one spot on a westerly aspect with wind drifts up to 5-10 cms (2-4") thick sitting atop some near-surface facets. The wind slab was 1F to P hard and was cracking locally around your skis, but cracks were not propagating any further.

- Shovel tilt test were getting clean shears at the interface between the wind slab and the old snow surface.

- Compression tests varied widely ranging from CT15 (10 taps from the wrist + 5 taps from the elbow) to CTN (no fracture.) Quality on one compression test was Q2, but mostly Q3. (This surprised us a bit as we were getting clean shears with shovel tilt.)

- Overall we felt the wind drifts were only appearing in small pockets at the elevations we were traveling (10,500') and they were not showing any energy with ECTN15 to ECTN20.

- Using the Strength -> Energy -> Structure model, we were finding (1) Strength = Strong. (2) Energy = Low. (3) Structure = Strong.

Few photos from today's group. This is Hannah taking a look at the wind slab from the easterly winds overnight.

Bridger demonstrating an extended column test.

Hannah demonstrating a compression test. Very subtle fracture in a layer of near-surface facets sitting just below the wind crust at 14/15 taps.

We're in good hands going forward with a group of strong, young riders developing solid avalanche awareness skills.

Today's Observed Danger Rating
Low
Tomorrows Estimated Danger Rating
Low