Northern San Juan
AvalancheJeff Davis · Dec 18, 2016 · Northern San Juan
Weather
Clear, Calm and Cold.
Snowpack
Obvious signs of insatiability were observed. Natural avalanches were observed on all aspect and at all elevations. The new snow has been drifted into large piles and large cornices have formed, even below treeline. Multiple snow test resulted in a failure at the new/old interface. Failures were hard, but propagated. A 5 cm surface slab created by the wind was also noted on exposed slopes near treeline. While on the skin track we experienced collapsing with the 3rd or 4th riders. At lower elevations the slab below the new snow is thinner than higher on the slope. That slab had difficulty holding the weight of a skier and collapsing was experienced near trees and low on the slope.
Avalanche
The largest natural avalanches were observed on south facing aspects of Silver Mountain. Other large slides were observed below cliffband and though coulior in the upper Waterfall basin. On open slopes below treeline near the Mustang ski run numinous natural avalanches were observed on east facing slopes near rock-bands. One skier triggered avalanche was also spotted from across the way.