Red Cone: Transitional Snow, Warming, and Snowpack Tests

SNOWPACK OBSERVATION
Submission Info
Forecaster
Sunday, January 28, 2018 - 12:15pm
Red Flags: 
Rapid warming
37° 35' 55.68" N, 119° 1' 23.52" W
Snowpit Observations
More detailed information about the snowpack: 

Several sets of weather observations on the way up Red Cone mid day to track warming near the snow surface: Site 1 was at 8750' on a SSW aspect of Panorama Dome at 1040am- Sky = Clear, Wind = Calm, Tair = 8 deg C, Tsurf = -3.6 deg C, T-20 = -2 deg C, Surface snow = Dry melt-freeze crust with small surface hoar on top, Ski pen = 10cm, Boot pen = 25cm. Site 2 was at 8944' on a SSW aspect around the back side of Lake Mary at 1105am- Sky = Clear, Wind = Calm, Tair = 9 deg C, Tsurf = -2 deg C, T-20 = -5 deg C, Surface snow = Dry but softening melt-freeze crust, Ski pen = 10cm, Boot pen = 25cm. Site 3 was at 9596' on a NNE aspect near the knoll E of Red Cone at 1145am- Sky = Clear, Wind = Calm, Tair = 5 deg C, Tsurf = -1 deg C, T-20 = -5 deg C, Surface snow =  Dry decomposing and fragmented grains, Ski pen = 20, Boot pen = 45.

Tracking surface conditions: snow was generally still dry winter snow on N and W aspects and moistening transitional snow on S and E aspects up to about 9900' where things depended more on direct sun exposure at the micro scale than general aspect (dry in the shade, moist in the sun). Above about 10,200' most surfaces except true S aspects with steeper inclines (facing more directly into the sun's rays) were dry. Even the S side of the summit was dry snow.

Profile dug on a NE aspect near treeline in an area where I had previously observed the persistent weak layer to test how things were responding to the sudden warming. Temperature gradient is trending less extreme throughout the pack. Stability tests still demonstrate the potential for sudden fracture initiation in small column tests, but no propensity for propagation (see attached profile).

No signs of instability anywhere. Conditions were variable in the way you'd expect of snow in transition from winter to spring like conditions. It could be time for sunscreen and t-shirts for a while.

Snowpit or crown profile photo or graph: 
Weather Observations
Blowing Snow: 
Air temperature: 
Wind Speed: 
Precipitation: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
More detailed information about the weather: 

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