Snow pits, Lee Vining canyon

SNOWPACK OBSERVATION
Dana Plateau
Submission Info
Forecaster
Thursday, January 24, 2019 - 1:00pm
Red Flags: 
37° 55' 28.1748" N, 119° 11' 32.7588" W
Snowpit Observations
More detailed information about the snowpack: 

We went for a tour up Lee Vining canyon today towards Dana Plateau.  No cracking, wumphing or recent avalanches were noted on our tour today.  Snow depths were quite variable today ranging from ~50 cm to over 300cm.  Today's weather was quite pleasant with temperatures above freezing, clear skies and light winds throughout the day.  
We made our way under the cocaine chute to check on surface conditions and found a mixed bag of windboard ranging from supportable to breakable.   We also noted ample debris from a large avalanche that appeared to occur during the 01/17-18 storms.   It’s hard to say precisely how large this avalanche was given the recent snow and wind, but I would put it at least at D2. 
I was able to dig in in two locations today.  My findings in each location were quite different.   On an east-facing slope at 10200’ I found a pretty uniform snowpack consisting of multiple layers of wind board. On a sheltered north-facing slope at 10100’ I found a more representative snowpack.  The height of snow at this location was 105 cm, and I was able to confirm both buried surface hoar and large loose facets making up the bottom of the snowpack. The surface hoar in this location was flattened and challenging to find and appeared to be rounding.  The SF was not reactive to compression tests; however, many shovel sheer tests highlighted this layer.  More concerning to me was the large, advanced facets roughly 60 cm from the surface.   This weak layer was reactive to compression tests and produced sudden planer results.  
While roller ball activity, wet, sticky snow/ melt-freeze crusts were evident on solar aspects shaded aspects are still holding good snow, and the descent down V bowl was pleasant. 

 

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
Clear
Air temperature: 
Above Freezing
Wind Speed: 
Light
Precipitation: 
Air temperature trend: 
Warming
Wind Direction: 
North
Accumulation rate: 
More detailed information about the weather: 

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