Southern San Juan
AvalancheChris Bilbrey · Feb 24, 2021 · Southern San Juan
Weather
Breezy day with temperatures in the 20s. Light drifting noted along ridgetops near and above treeline.
Snowpack
Snow depths above 10,000 feet on multiple aspects around Wolf Creek Pass range from 150 to over 200 cm's deep. Probing on a north aspect near treeline, the top 40 to 50 cm's consist of a F to 4F slab (top to bottom) sitting above a thick 1F layer. We found generally good bonding between recent storm layers on north to east aspects with Compression Test only producing break failures. However, we did identify a near-surface facet layer within the top meter of the snowpack on northwest through north to east-facing slopes that could be a concern if we receive a big load in the near future or drifting building stiffer surface slabs. Southerly and west facing slopes have multiple crust buried below the surface. We noticed prior slope wide cracking on south and southwest slopes near treeline. We suspect these cracks formed naturally from our recent warm up or from riders traveling above collapsing buried crust with faceted grains below. No slides ensued. Widespread surface hoar formation on shady, below treeline slopes ranging from 10 to 15 mm. We also found 4 to 6 mm surface hoar in isolated areas below ridgelines near treeline. On east-facing slopes, surface hoar formed above a melt-freeze crust. It'll be important to evaluate the presence of these delicate and worrisome feathers as they get buried by snowfall. Cornices have grown large in the past month and these beast should be given a wide berth during warmups and we transition closer to spring.
Avalanche
One old crown line visible on a steep north-facing slope near treeline. Looks to run during our last storm cycle between 2/10-17.