Small wind slabs below Sherwin Ridge

Abobve Mammoth Rock
Submission Info
Wednesday, December 25, 2019 - 11:30am
Above Mammoth Rock 37° 36' 34.3764" N, 118° 59' 29.9256" W
Snowpit Observations
More detailed information about the snowpack: 

Wanted to .get some sense of what the new snow is doing and ski some Christmas powder.  Started below Mammoth Rock at 830am. Light breeze, clear skies and brisk temperatures. Followed skin track to top of Sherwin Ridge. Ski pen 30-40cm. 

Mostly unaffected, dry snow in the N facing trees. Hand pits generally required strong force or my hand would just pull through the new snow. Forgot to measure new snow depth, but I'd estimate 30-40cm of new.

No instabilities noted in the trees. However, the NE slope between the skin track and Mammoth Rock bowl was progressively more wind affected as we climbed higher. At 9600 ft, wind slab was apporximately 5 cm thick and resistant to ski cutting and stomping. Higher up, in more exposed areas the wind slab was 15cm along the ridge.   Localized cracking under my skis was noted but nothing that propagated, even with forceful stomping. This dense slab felt hollow and was sitting on soft, 1 finger dense snow. Open slopes in Mammoth Rock bowl looked fairly wind affected.

Once on the ridge top, we did noted one natural vs skier triggered slab that ran <100 ft with a crown varying from 15cm to over 35cm at its thickest (see photo). This slid on a NE aspect, with a few blocks large enough to possibly injure a skier. I tested a similar slope and had some cracking under my skis but nothing that propagated (see photo). 

Light wind starting by 1130 with surface transport near the ridge top.

Hero powder skiing in the trees back to the car. 

Snowpack photos: 
Localized cracking on wind loaded slope just below Sherwin Ridge.
Small slab avalanche below Sherwin Ridge.
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