Northern San Juan
SnowpackSusan Hale · Mar 21, 2013 · Northern San Juan
Weather
Out during a bit of a lull in the storm. A very hot sun poked out briefly a couple of times - instantly warming exposed surfaces on the E up-track. Otherwise wx conditions were generally mostly-cloudy with gusty westerly winds and quite warm (30F at Pass level). Witnessed wind gusts moving significant amounts of snow on nearby summits. There was top-loading and X-loading onto a variety of aspects near and above TL. Mainly affecting NW-N-NE-E aspects. Not much snow moving below TL. On the descent the storm moved back in with a return of moderate snowfall and wind that lasted approx another 1-1.5 hours - becoming partly cloudy after 3pm.
Snowpack
Height of new snow was variable depending on aspect elevation, from 4"-6" on the Easterly up-track BTL; to 6"-8" near and above TL. (There were a few pockets behind tree or terrain catchments with up to 10+" new.) The existence of a slippery interface between old and new was also variable - generally found on colder aspects. New soft-slab formation was mainly confined to open wind exposed areas near and above TL. Some drifts of slab were up to 10"-12" We chose to steer clear of these open slopes and ski down more protected terrain. We briefly had visibility to observe one Natural SS avalanche on a NE aspect above TL (see avalanche obs). Expect this new snow to sluff easily with this afternoon sunshine and warm temps - esp from steeper sunny aspects.