Northern San Juan

Avalanche

Ben Graves · Jan 17, 2016 · Northern San Juan

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Weather

Clear, Northwest winds, around 10-15mph. Accumulation was around 5 inches in 24 hrs and 9 in last 48 hrs. Southeast facing slopes. Elevation ~12,800

Snowpack

Pit dug on similar SE slope at 11,900. Tests revealed a reactive 5-9" new snow layer that failed while cutting the column. Failure was on the new-old snow interface. Very sun/wind affected crust. About 2 ft of sugary snow at the bottom of the pit.

Avalanche

NW winds caused a windloaded cornice to collapse. Looked like the cornice-fall stepped down and caused a large R2 D2 avalanche in the bowl. Start zone was about 45 degree. Bowl becomes 35-40 degrees. Ran over 2000 vertical feet. Ran to grown. Probably happened in the am hours on Sunday.