Wind slab in VA lakes

SNOWPACK OBSERVATION
South Peak
Submission Info
Forecaster
Wednesday, December 18, 2019 - 2:00pm
Red Flags: 
Recent loading by new snow, wind, or rain
38° 2' 25.7856" N, 119° 15' 26.2008" W
Snowpit Observations
More detailed information about the snowpack: 

It was a beautiful day in the Virginia lakes area today. Mostly clear skies with brisk temperatures and light to moderate southerly winds. I was aiming for Dunderberg and was hoping to get a feel for some more southerly aspects today; however the shift in the winds has removed much of the snow from the SE face, and I shifted towards South peak. 

There were signs of wind transport throughout my tour today, even in well-protected areas below the tree line. I found a max of 90 cm in snow depth today with the average being more in the 50-60 cm range. The low-density surface snow from a couple of days ago has been replaced with hard wind board and raised tracks in more exposed areas, and ribbons of grabby wind textured powder in sheltered trees and relatively protected catchment zones. 

I dug in at 10,650’ on a wind-loaded north facing aspect and found some concerning wind slab. See attached pit profile and video.

HS= 85 cm

Ski pen=0

Boot pen=~5~ (though a good kick through the supportive wind board and it was closer to 50cm)

I found about 25-30 cm pencil hard wind slab over fist hard faceted rounds. And my tests found this layer to be reactive to easy-moderate force. ~CT11-SP-Q1, ECTP7, ECTP11(x2)~ All tests failed just below the windslab, and all exhibited sudden plainer results. This got my hackles up a bit. I had a couple of other interesting takeaways from my pit today. One is the presence of faceted grains. The combination of a thin snowpack and cold air temperatures has resulted in a steep temperature gradient, which in turn is weakening snowpack. Second, my observations today found the rain/MF crust seems to be deteriorating quite a bit. I suspect the same temperature gradient is responsible for this development. While adding to the sensitivity of the wind slabs I observed today, I suspect the weakening of the surface snow may help the skiing conditions in the short term. But It will certainly be worth keeping an eye on what’s happening deeper in the snowpack if and when we start to see more precipitation.

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Snowpit videos (tests, etc): 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
25% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
None
Air temperature trend: 
Cooling
Wind Direction: 
South
Accumulation rate: 
None
More detailed information about the weather: 

Cold temperatures, light to moderate winds and mostly clear skies made for a beautiful brisk day. Some blowing snow was observed on ridge tops however available snow seems to be limited. 

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