Southern San Juan
SnowpackChris Bilbrey · Dec 26, 2019 · Southern San Juan
Weather
Stunning Colorado day - bluebird skies, cool temperatures, and calm winds. Evidence of previous wind-drifting in favored alpine areas. Many open slopes and alpine start zones looked phat and heavily wind-loaded.
Snowpack
We found up to 18" of new snow near and below treeline and drifting between two and three feet below ridges and in isolated leeward terrain. Despite the low density storm snow and recent strong south to southwest winds, drifts up to 12,000 feet remained soft where we traveled. We saw evidence of heavier drifting and surface texture in favored areas at higher elevations. We identified two buried surface hoar layers on a north-facing, wind-sheltered slope that were unreactive in long-column test. The upper layer is the most preserved and concerning with another strong storm knocking on the door step. We found a troublesome trap door set up in the alpine where near-surface facets sit below a pencil hard wind-slab. At present, the surface slab is soft and produces more sluffing than slab release in steeper terrain. As the slab thickens and stiffens with additional snowfall over the next 48 hours, it could become reactive producing larger slides in wild snow.