Northern San Juan

Avalanche

Colin Mitchell · Dec 3, 2019 · Northern San Juan

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Weather

Morning clouds diminished through the day. Quite warm with light winds.

Snowpack

HS varied between 40 and 65 cm. The snow has been settling and gaining cohesion and was generally supportable to skis, but not to boots. 10mm+ surface hoar was widespread in open terrain, and survived the day in sheltered and low-angle areas. Where the surface hoar didn't form, I found a thin layer of well-developed facets on the surface. Last week's snow was faceting, but older snow was holding up pretty well. I was able to find the October layer in isolated areas by probing. I did not find any large areas where this layer was continuous. It appeared and disappeared twice in my profile wall, and didn't react to snowpack tests. I did get some localized collapsing in the trees, the largest about 25 feet in diameter. There were some rollerballs and small point releases in the rocky terrain above my pit site. Otherwise, no signs of instability observed.

Avalanche

I observed some rollerballs and small point releases from the rocks on steep, sun-exposed NTL slopes by midday.