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Observation: Park City Ridgeline

Observation Date
2/10/2018
Observer Name
CBrown
Region
Salt Lake » Park City Ridgeline
Location Name or Route
PC Ridgeline
Weather
Sky
Broken
Precipitation
Moderate Snowfall
Wind Direction
North
Wind Speed
Light
Weather Comments
Sky was OVC to SCT through the day. Periods S2 snowfall, about 4cm during 1.52hrs. Light winds with gusts in the moderate to strong range. Cool temps ~8C at 12:00.
Snow Characteristics
New Snow Depth
4"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments

About 2" of new overnight at 8,800', an additional 2" fell during periods of moderate to heavy snowfall between 13:30 and 15:30.

Red Flags
Red Flags
Wind Loading
Poor Snowpack Structure
Red Flags Comments
The structure where observed was some of the weaker snow I have seen latley. Advanced and large grain depth hoar above and below the TRC (thanks giving rain crust). Shallow and not much rounding going on. Example of shallower weaker snowpack on the PC side of the wasatch.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments

The snowpack seems to be pretty tired and unreactive at this point, but the structure is still there, and after wailing on an ECT 5 additional taps after the 30 for the test, saw full propagation 23cm from the ground on the DH below the TRC. I have found ECT's to be somewhat unreliable stability tests/data this season. Low probability, but still high consequences.

Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #2 Comments

With new light density snow available for transport and the moderate winds I would expect wind slabs may have been forming today in specific areas, and maybe an issue tomorrow morning before settling out.

Snow Profile
Aspect
Northwest
Elevation
8,800'
Slope Angle
23°
Today's Observed Danger Rating
Low
Tomorrows Estimated Danger Rating
Moderate