Manto nivoso

Northern San Juan

Chris DicksonNorthern San Juan
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Weather

Moderate snowfall with a few lulls mid-morning. Steady northwesterly winds were transporting snow along ridgelines. Temperatures in the teens warmed to mid-20s by midday.

Snowpack

The most sensitive slopes were the ones that harbor a thin melt-freeze crust/facet combination. I experienced this setup on a northeast-facing near treeline slope. As I approached a spot to dig a snowpit, I felt a rumbling collapse that broke off a piece of cornice along a ridge about 50 feet away. When I dug down, I found that the slope failed where the new snow rested over a thin and fragile melt-freeze crust with well-developed facets underneath it. Tests on this layer resulted in CT1 SP and ECTP1 results.... in other words, touchy. This area receives significant wind-drifting and the new snow was 50cm thick. These are the slopes I'm most concerned about right now. Elsewhere, in lower, more sheltered terrain, I didn't observe any slab quality to the new snow yet. Was only able to glimpse the alpine through clouds, but I did not observe any recent natural avalanche activity on my tour.