Shallow coverage, weak structure in VA Lakes

SNOWPACK OBSERVATION
Submission Info
Forecaster
Thursday, December 24, 2020 - 1:00pm
Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
38° 2' 25.278" N, 119° 15' 11.988" W
Snowpit Observations
More detailed information about the snowpack: 

Low expectations helped the fun factor as we toured up to tree line on South peak in the Virginia lakes area today.  

Leaving the car at 9700’, I noted about 20 cm of snow on the ground and surface conditions were heavily affected by the recent strong winds even in sheltered areas at lower elevations. Along our ascent we noted snow depths ranging from bare ground to a max measured depth of 60 cm. The average depth seems to be around 30-40 cm (12”-15”).

We noted a similar structure as has been reported throughout the range with a shallow weak structure. I initiated a large, slope scale collapse on the ascent at around 10,400’ on a NE aspect as we approached tree line. Digging in nearby I found about 50 cm of snow with about 35 cm of right-side up decomposing grains resting on top of 14 cm of fist hard, well developed facets. This is unsurprising given what we have seen throughout the forecast area. Stability tests confirmed the weak nature of the snowpack with propagating results under easy force. (ECTP-5) My feeling with regard to this weak structure is that we will need a new load of snow to really awaken the avalanche dragon, but it is still concerning and certainly has my hackles up.

The largest hazard at the moment remains the thin coverage. I uncovered more than a few rocks as I tio-toeed back to the car. Adding some challenge to the conditions are the variable surface textures which ranged from a thin wind skin to, to breakable windboard ~5 cm thick to fully supportable wind board. While we were able to sniff out some areas with soft wind textured snow the extreme variability kept us on our toes and moving with extreme caution.

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Snowpit videos (tests, etc): 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Above Freezing
Wind Speed: 
Calm
Air temperature trend: 
Cooling
More detailed information about the weather: 

Mostly cloudy skies prevailed today with mild temperatures and not a breath of wind near and below tree line.

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