Southern San Juan
SnowpackChris Bilbrey · Dec 14, 2022 · Southern San Juan
Weather
Cold and sunny. Moderate northerly wind contributed to drifting along ridgetops.
Snowpack
We found around 8 inches of new snow from our last storm. December snowfall now accounts for greater than half to two-thirds of total snow depths. The overlying slab continues to settle and stiffen, and this has contributed to a less talkative snowpack. East and southeast aspects near treeline provided the most consistent collapses and were softer rumbles. In this scenario, the overlying slab is gaining strength faster than the buried weak snow - a classic Persistent Slab avalanche problem. As long as a poor structure exists below, it remains possible to trigger a larger slide, especially if you find a shallower area of the slope where weak facets are closer to the surface. Targeting east and southeast aspects, faceted snow crystals took more force to fail in the stability test, and in some instances, the quality of failure is dirty versus clean, snappy failures. Probing across slopes is still a simple way to gauge if weaker snow lurks below. The buried crust can be felt probing around and have a spooky trap door setup with softer facets both above and below the crust. Northwest winds on the backside of our recent storm system were drifting and blowing snow onto easterly aspects forming stiff, windboard surfaces in isolated areas. These were stubborn and reluctant to fail with ski pressure as fresh Wind Slab avalanches where we traveled. Above the treeline, we saw lots of slopes that look good from far away but are still far from good in terms of coverage. Lots of scouring and stripping on southerly terrain and overall deeper and broader snow coverage on northerly and easterly aspects with evidence of surface texturing.