Southern San Juan
SnowpackChris Bilbrey · Jan 14, 2020 · Southern San Juan
Weather
Strong southwest winds were blowing and sublimating snow along ridgelines and peaks. Lots of snow plumes visible throughout the day. Temperatures warmed under sunny skies. By the late-afternoon, easterly and south-facing slopes formed a thin zipper crust after transitioning from sun to shade.
Snowpack
Once again, the alpine got pummeled by strong west to southwest winds producing lots of blowing snow, plumes off ridges and peaks, and sublimating snow into the atmosphere. We did not climb to timber line, but noticed isolated pockets of wind-drifted snow forming around that elevation with swirling winds and even the random upslope eddy-effect wind. Below treeline, the snowpack continues to show signs of weakening and faceting below recent storm snow - some places we could poke our ski poles all the way to the ground. This has contributed to generally safe conditions at the moment below treeline. Recent low-density snow accumulations have not added enough of a load to increase instability or form a cohesive slab below treeline. The catch 22 here is that the snowpack at lower elevations will have a difficult time supporting a large, future storm load. As we climbed above 11,000 feet, we began to feel the effects of drifting and stiffening of surface slab. Isolated cracks below our skis were observed in isolated deeper drifts but none propagated outward. We also observed two collapses on an east-southeast and southeast-facing slope. The snowpack in this particular area is much thinner than other areas nearby and multiple near-surface facets and faceted crust found in the top 50 cm's. Although our long-column test didn't produce propagating test results, a general weak structure, collapses, and most recent avalanche activity occurring on east and southeast-facing slopes was enough for us to not continue higher in elevation where more widespread drifting was anticipated.