Southern San Juan
SnowpackChris Bilbrey · Dec 15, 2022 · Southern San Juan
Weather
Single-digit temperatures to start. Sunny skies allowed temperatures to climb into the low-20s by midday. Moderate westerly winds along ridgelines contributed to blowing and drifting snow onto easterly-facing slopes.
Snowpack
Overall snow depths are much shallower in the Parrot Peak zone than in other places we've traveled this season up the canyon. Additionally, buried weak snow (November drought facets) below December snowfall is softer and appears more likely to fail from an additional new snow load or the weight of a rider. Like many other places in the San Juan Mountains, snowfall over the first half of December now accounts for a majority of the snowpack on north to east-facing slopes. Southeast aspects near and below the treeline in this area are too thin to pose much avalanche hazard and not deep enough to support over-the-snow recreation. Uphill travel became arduous once we climbed above 10,000 feet and starting breaking into deeper, softer layers even with our skis. Boot penetration was to the ground throughout our travels. Lots of cracking and collapsing on terrain features over 32 degrees and in heavily wind-drifted areas. Signs of unstable snow were localized, but this may have been a factor of shallow snow depths and lots of vegetation still poking through the surface. The Compression Test and Extended Column Test (ECT) evaluating sensitivity of buried weak facets both produced failures with 11 taps. Our ECT column "cash drawered" into the pit after the crack propagated across the column. Westerly winds were blowing and drifting snow at upper elevations and even stiffened the snow surface in open areas and aprons below avalanche paths.