Manto nevoso

Northern San Juan

Chris DicksonNorthern San Juan
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Weather

Overcast skies and temperatures in the 20s with a light breeze out of the southwest.

Snowpack

This area received less snow over the holidays than Red Mountain Pass and, as such, the slab that formed over our very weak December drought layer is less thick, stiff, and cohesive below and near treeline. On sheltered north-facing slopes steeper than 35 degrees, it seems like loose avalanches that gouge into deeper weak snow are more likely than a slab. UNLESS, you find a more open slope that has been stiffened by wind/sun/settlement/etc, which is much more likely in the near-treeline elevation band. As I approached my dig site, near treeline, I triggered a small collapse with cracks breaking 15 feet away. In this pit, I found a 4-finger-hard slab about 40 centimeters down from the surface sitting over very weak facets. An extended column test failed on isolation on this layer, and a compression tests resulted in a sudden planar failure on the 12th tap on this same layer. Clearly, all signs point to poor structure and the perfect setup for Persistent Slab avalanches within the top 50 centimeters of our snowpack. The sensitivity of this setup may be decreasing but the consequences remain the same: a dangerous slab avalanche that could gouge deeper into the snowpack, becoming larger as it goes. The freezing rain crust that formed on 12/28 around Telluride is also present in Ophir, but luckily it appears to be breaking down rapidly here and does not negatively impact riding conditions (but you can hear it crackling!).