Northern San Juan
AvalancheScott Roberts · Jan 25, 2019 · Northern San Juan
Weather
Sunny, cold wind
Snowpack
At this location, newly fallen light powder observed on 1/24 had somewhat settled and was covered by stiffer wind-deposited snow by 1/25
Avalanche
Two skiers ascended a southern ridge of peak 12,271 from Prospect Gulch. We confined our uphill and downhill travel to the lower angle ridgetop/rib, deliberately avoiding the steeper south and southwest facing gullies on either side of the ridge. As the skier #1 descended a moderate SW slope from the ridgetop, he immediately remotely triggered a large slab avalanche approximately 500 feet to the west of the skier on a steeper SW slope at the head of a gully. The avalanche was far enough away to not be immediately visible to the skiers, but the sound of moving snow and snapping branches/trees was audible, soon followed by a visible plume of snow. We estimated that the avalanche crown extended at least 800 feet across the slope propagating across two different gullies. Large avalanche debris extended out of sight down the gullies but did not run all the way to the Prospect Gulch road. Due to safety concerns, the skiers did not approach the avalanche site or crown to investigate the bed surface, but the crown appeared to be 3 - 5 feet deep and at an elevation of 12,100 feet. No other skiers or tracks were seen in the immediate vicinity that would have indicated that other parties were below the slope and could have been affected by the the avalanche.