Northern San Juan

Avalanche

Jeremy Yanko · Jan 13, 2023 · Northern San Juan

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Observation photo 1Observation photo 2Observation photo 3Observation photo 4

Weather

Very mild January-thaw day under a thin haze

Snowpack

Traveled on a mostly west aspect from ~10-11k mid morning into early afternoon. This slope was holding a fairly consistent snowpack depth ranging from 90-110cm, in the below treeline elevation band. The southwest facing ridgeline adjacent to this path, already developed a 5cm P- crust from the previous onslaught of mild temps and blue skies. By 1pm, you could wring water out of the surface snow as temps looked to get well above the freezing mark in this area. Due west surfaces definitely moistened today likely lending to a nice breakable lens for the incoming storm to fall on. One snowpit near the top of the slope gave way to hard snowpack test score results by compression tests. Propagating results in an ECT were achieved at "32" with some forced loading steps. No red flags were encountered other than seeing the lemons that exist in the profile at this location. Sensitivity to triggering is easing yet the main persistent weak layer of concern here is only insulated by an 80cm slab at present.

Avalanche

Two Natural slab avalanches assuming to have been pushed by intense wind loading on the 11th.