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Observation: Park City area mountians

Observation Date
12/15/2016
Observer Name
B
Location Name or Route
Park City Area
Weather
Sky
Overcast
Wind Direction
Southwest
Wind Speed
Moderate
Weather Comments
Warm evening on the 14th leading into another Warm day on the 15th. Overnight Lows remained in the mid 40's at 8000. WSW to SW Winds in the Moderate Range a Mid Elevations with Light Wind Blown and or Transport. In the Upper Elevations and on the Ridgelines Plumes of Snow could be observed throughout the AM Hours. Rain began in the early afternoon with Rain reported to at least 9000. At 2000 Hours the Rain/Snow Line was 8500 feet with S3 Snowfall occuring at 8700.
Snow Characteristics
Snow Surface Conditions
Wind Crust
Melt-Freeze Crust
Damp
Snow Characteristics Comments

Surface Snow was Damp at 1100 Hours at 8700 feet. There was a 1.5mm M/F Crust just below the Surface Snow, up until Noon when we exited; and most likely it melted during the day and rain. Of Note, at 1100 Hours at the same Elevation the entire Pack was Dry besides the top cm. Also of note, 10 cm of Dry Basal Facets were observed.

Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Wind Loading
Rapid Warming
Poor Snowpack Structure
Red Flags Comments
Wind Loaded Hard Slab Avalanches reported were obvious signs that Upper Pack Weak Layers continue to be reactive. Heavy Snowfall as reported above signifies the arrival of the storm and forecasts indicate excessive Water Available. Rapid and Significant Daytime Heating helped Widespread Wet Loose acitivity below 9000 feet observed. Poor Snowpack Structure noted in Snow Pit with buried NSF's reactive at 19 cm down with CTM Scores. ECTN appear to indicate Slab lacking propencity to Propagate at this interface.
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #1 Comments

See above

Avalanche Problem #2
Problem
Persistent Weak Layer
Trend
Increasing Danger
Problem #2 Comments

Additional substantial Loading as forecasted most likely will reactivate Mid Pack buried NSF's; and as well promote the possibility of Deep Slab Activity in Upper Elevation Northerly facing terrain.

Continued Rain in the Mid to Lower Elevations may allow for more Wet Loose, and by Friday am, Wet Slab possibilities may be becoming Likely on all aspects, especially the North Facing terrain that is experiencing Water Percolation for the first time.

Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
High