Northern San Juan
SnowpackAmy Pertuz · Jan 27, 2022 · Northern San Juan
Weather
Clear skies in the morning gave way to light snow by 11am. Accumulation of 2" over the day. Winds did not create any significant blowing snow in areas travelled
Snowpack
Surface Hoar from Jan 21 has been well preserved on many aspects and elevations in these drainages. The 3" that preserved this SH last week on the 21st was enough to prevent it's destruction in this location. This ~3mm SH layer was seen on W, NW, N, NE, E, SE aspects from 9500' to 11, 800'. On more northerly aspects, this layer is part of a larger volume of surface snow (top ~15+ cm) which is faceting generally, making for easy triggering of small dry-loose slides (D1 or smaller) in surface snow on N'ly aspects. On more E'ly aspects, the snow which capped this SH settled and then was topped by recent low density snows, making for a very delicate interface about 6cm below the surface. S'ly aspects had a similarly weak facet/crust combo in the upper 6cm but couldn't find any evidence of SH. E and SE aspects both had a very problematic layer cake in the upper 10cm of the snowpack which will perform poorly with much load on it. On more N'ly aspects, the surface is also weak from faceting, but is much more uniform, with no harder layer directly on top of the prominent weak layer.