Sherwins - Ridgetop wind loading and cornices

Submission Info
Monday, March 23, 2020 - 4:30pm
Red Flags: 
Recent avalanche activity
Recent loading by new snow, wind, or rain
37° 36' 18.882" N, 118° 59' 13.9956" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up the Sherwins lake afternoon to check on wind slabs.  Winds were blowing snow at all elevations, but below the ridgeline they were fairly erratic in direction and I couldn't find anywere that was loading to a concerning extent.  At the ridge however, SW winds were blowing consistently at a solid moderate speed blowing snow into the northerly facing terrain.  Cornice's were growing, some had been triggered earlier in the day, and were growing back.  Stomped on one (see video) that triggered a 6-8" wind slab just below the ridge that propogated about 35ft wide (R!-D1), and didn't run too far below the upper most small trees.  The concerning sensitive wind deposited snow was limited to just below the ridgeline.  Got a report ealrier in the day that a small avalanche occured naturally at the ridgeline above mammoth rock bowl, and was able to check it out with binoculars, and it appeared to be quite thin (~4-6"), and about 50ft across (R1-D1).  Evidence of the crown was gone when I got toward the ridgeline 5 hours later, but the debris could still be seen.

It appeared that an inch or two of dense snow fell throughout the day here, but hard to tell with the winds.  Relatively warm, see icycles frowing in the trees pic.  Where snow was not newly wind deposited it was quite well bonded.  Dug one pit ~9,700', north aspect, to check on underlying structure.  Right-side-up well bonded snow from the past week+ (fist to 4finger to 1finger) ontop of thick crusty layer ontop of ~5cm loose faceted 4finger snow.  ECT tests did not fail under standard taps, but after whaling on the column a handful more times, column failed and propogated across this loose faceted layer.   

Snowpit or crown profile photo or graph: 
Snowpit videos (tests, etc): 
Weather Observations
Blowing Snow: 
Cloud Cover: 
100% of the sky covered by clouds
Wind Speed: 
Wind Direction: 
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Some snow showers, but light accumulation.

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