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Observation: Porter Fork

Observation Date
3/3/2018
Observer Name
P Diegel
Region
Salt Lake » Mill Creek Canyon » Porter Fork
Location Name or Route
Main Porter
Weather
Sky
Overcast
Wind Direction
Southwest
Wind Speed
Light
Weather Comments
On the leading edge of the storm light variable wind when I started, rapidly increasing by the time I was done
Snow Characteristics
Snow Surface Conditions
Dense Loose
Snow Characteristics Comments

Highly variable snow surface - I was about 200 ft below the ridgeline on a lee slope with a wide range of wind effect from the last 24 hours

Red Flags
Red Flags
Wind Loading
Poor Snowpack Structure
Red Flags Comments
The snow structure was not as dramatically bad as I expected based on reports
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #2 Comments

Wind effect was limited to an easily breakable 2-4 cm surface in the spot I dug. Between that point and the ridgeline the snow surface ranged from soft and dense to supportable wind board

Snow Profile
Aspect
Northwest
Elevation
9,200'
Slope Angle
27°
Comments

Stability tests: Several compression tests and an ECT yielded no results but several shovel shear tests showed a very easy failure with Q2 shear, 1 of 3 failing about 40 cm down and again at 75 cm and 2 others failing 75 deep, both depths failing on 4 finger hardness small facets below a pencil hard layer. Total snow depth 175 cm. I've never noticed such an easy shear failure with no compressive failure.

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