Northern San Juan
AvalancheAmy Pertuz · Mar 24, 2020 · Northern San Juan
Weather
High solar radiation but steady breezes, light to moderate, out of the South, shifting towards West, kept things fairly cool near and above treeline.
Snowpack
Yesterday’s 4” of new stayed dry and cold on many slopes above 11,300ft today, despite strong sun. The sun did set off a round of dry loose and wet loose slides, all smaller than D2, on E-S and some W aspects, generally lower elevations in areas with rocky outcrops, running on the sun crust that formed during the brief sunny spell on Sunday. On a Westerly slope above treeline, the recent storm snow has settled into a more cohesive slab than on other colder aspects, though the surface remained dry. A crust/facet combo buried 60 cm below the recent storm snow on this W aspect showed propagating failures in tests. Another old facet layer without a crust was found on a NE slope above treeline under 85 cm of recent storm snow. This failed but did not propagate in tests. The slab above it was less cohesive. A new RR crust was seen below dry surface snow on an E aspect at 11,700ft. Lots going on out there, plenty of good surface conditions remain on upper elevation, colder slopes. We kept slope angles under 36 today.
Avalanche
No new slabs. No signs instability.