In-storm Instabilities around Old Mammoth Rd.

Old Mammoth Road
Submission Info
Sunday, February 3, 2019 - 2:15pm
Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
Old Mammoth Road 37° 37' 11.0352" N, 118° 59' 58.4124" W
Snowpit Observations
More detailed information about the snowpack: 

Followed trenched out skin track from the end of Old Mammoth Road to the Mammoth Rock Trail TH. Poked out into glades beneath Mammoth Rock. At 1230 it was snowing lightly with strong winds. Hand shears yielded clean restults, with light force in the upper 6 inches of the new snow. Failures within new snow were at a slight density change. Snow was generally upside down. A quick pit was dug on a NE aspect at about 8500' where compression tests x2 yielded CTE SC results down 15 cm at a similar density change (F+/F layering). The red flags were already present to not venture higher into the Sherwins today, but wanted to check out new snow in a low angle, open location. On Panorama Dome I intentionally triggered a soft windslab avalanche (R2D1) on a steep roll receiving heavy wind loading. The slide was approx. 100' wide by 50' in length with about a 1 foot crown. The slab was 4F- in hardness and broke within the wind deposited snow. In the same area I experienced cracking and collapsing within the new snow. Winds were strong and gusty out of the SW on Panorama dome with snowfall periodically heavy. Wind loading of lee aspects was sustained.The skiing was a real challenge today with a punchy surface and generally deep conditions. Keep your tips up!

Snowpack photos: 
Weather Observations
Blowing Snow: 
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
Less than 1 in. per hour
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