Southern San Juan
SnowpackKrista Beyer · Mar 28, 2024 · Southern San Juan
Weather
Temperatures at nearby Columbus Basin (10785ft) show a max temp of 30 degrees on 3/27 and 39 degrees on 3/28. The 24 hour wind average was 15.6 mph SSE with a peak gust of 33 mph. Despite the winds, no blowing snow was observed at ridgeline.
Snowpack
Columbus Basin received 0.9 inches of snow water equivalent (SWE) during this storm, corresponding to an observed 15-18 inches near and above treeline. This new snow has settled to about 6-8 inches near treeline. The initial snow arrived with low winds at the start of precipitation on the 24th; overnight into the 25th, winds increased with additional precipitation. These wind/snow conditions appear to have created an inverted slab in the new snow (strong over weak) that produced propagating results on the 25th. Three days later, the structure of the inverted slab persists, but time and warm temperatures have reduced the reactivity and halted propagating results. The attached media shows two pits dug near treeline one on a ENE slope the other on a SE crossloaded terrain feature. The ENE pit shows the inverted slab is breaking down and becoming overwhelmed by a melt-freeze crust. The SE pit was dug near an area with recent evidence of wind slab activity (skier presured break in the top 5cm). Suprisingly the cross-loaded feature maxed out my probe indicating that the prevailing winds like to cross load this slope throughout the season. See attached media for pit results. On north slopes, the inverted slab can be found, but proved to be unreactive to ski pressure, a few hundred feet below the ridge the inverted slab dissapears.