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Observation: 10420

Observation Date
2/21/2017
Observer Name
John Mletschnig
Region
Salt Lake » Big Cottonwood Canyon » 10420
Location Name or Route
Mill F East to 10420
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Direction
Southwest
Wind Speed
Light
Snow Characteristics
New Snow Depth
1"
New Snow Density
High
Snow Surface Conditions
Powder
Wind Crust
Snow Characteristics Comments

Heavy snow... Maritime!

Red Flags
Red Flags
Wind Loading
Cracking
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #1 Comments

lee and local to mid and high ridges. slabs were very stiff today with high new snow density, high temps and high humidity.

Avalanche Problem #2
Problem
Persistent Weak Layer
Problem #2 Comments

Buried near surface facets from prior to the last storm sit on top of a rain crust below 9500'. The facets seem most pronounced where melt layer recrystalization process was most pronounced at mid elevations where rain put in lots of heat in the snowpack. It will be interesting to see whether this layer becomes a player as large loads are added to the snowpack in coming days. The upper limit of this layer acted as a resistant shear plane as well as the lower limit of it against the rain crust which appeared to have slightly larger faceted grains (also resistant planar in shear).

Our buried surface hoar layer from a few weeks back was also still intact in our protected pit location at mid elevation though it was not reactive to stability tests. This layers seems fairly well bridged out by overlaying rain crusts.. for now.

Snow Profile
Aspect
Northeast
Elevation
8,900'
Slope Angle
20°
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates