Northern San Juan

A skier triggered avalanche on a northeast near treeline slope. The avalanche appears to have been triggered during the storm, was small in size, but was likely fast running. In addition, I saw a handful of small natural avalanches on NW and NE slopes. These originated in steep rocky terrain.

This storm produced and brought totals close to the projected numbers from the National Blended Model for much of the Northern San Juans. This was a welcome sight after Wednesday's storm underproduced in our area. Red Mountain Pass measured out at 15.5 inches of snow since the 11th at 1.15 in Snow Water Equivalent (SWE) (2 inches at .2 SWE from the 11th). Both storms were warm. Snow on the 13th came in colder and ended heavier as the day progressed. South/southwest winds were enough to drift during the storm (avg speed 14, peak gust 39 mph at Putney), but no drifting was observed today as they shifted north.

Recent snow sits above weak facets. Near and below treeline shady slopes, the snowpack is fully faceted below the recent snow. Instabilities are related mostly to recent snow with the chance for gouging loose avalanches on very steep slopes that haven't seen previous traffic. This has been the season of "new snow instabilities" on weak layers. This will change next week if the snow forecast produces. With another load, we will move into a regime we know well most years: a persistent slab problem defined by a connected layer sitting above very weak facets with a new load on top.