Snow Observations in Lakes Basin

SNOWPACK OBSERVATION
Lakes Basin
Submission Info
Volunteer Observer
Wednesday, March 18, 2020 - 3:15pm
Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
37° 34' 41.1852" N, 119° 0' 14.9904" W
Snowpit Observations
More detailed information about the snowpack: 

Toured today up Lake Mary Ridge and connected the ridge towards Sister Chute and TJ/Hammil Bowls. The previous track had been blown in and had been replaced in exposed locations by 40-50cm of new, 4F dense snow. Shooting cracks between 6-8' were observed when stomping on windrolls and small test slopes indicated a stiffening wind slab atop softer new snow. This slab was between 10-15cm and was only reactive locally. 

Further up, trail breaking was quite challenging, with between 30-50cm ski pen and boot pen of 90cm. While skinning at 10400' on NE aspect around 28 deg. we observed one slope-wide collapse with an audible whumph as well as one more localized collapse. Hand shears near this location also identified isolated, stiffer wind deposited slabs that failed upon isolation within interstorm layers down approx. 80cm. Large cornicing was evident along ridgelines, guarding access to some of the steeper chutes that lead into the large bowl features.

We skied 30 deg. terrain and had generally good riding conditions where the stiffer surface snow could be avoided. A couple folks were getting after it in steeper and more consequential terrain in this area though aside from a natural likely shallow windslab that failed in thin terrain adjacent to TJ Chute there were no observed avalanches.

Snowpack photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
None
Air temperature trend: 
Static
Wind Direction: 
Southwest
Accumulation rate: 
More detailed information about the weather: 

At 3:30pm, at 10600', sky cover was broken, Air temp was -9.3c, precipitation was nil. By 4:30pm sky cover was obscured with S-1 snowfall rate

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