Southern San Juan
SnowpackChris Bilbrey · Jan 12, 2023 · Southern San Juan
Weather
Single-digit temperatures to start. Northwest winds were blustery during the morning finally subsiding around 11:30 am. Strong winds produced long-running snow plumes off peaks. By mid-day, the temperature had moderated into the upper 20s under sunny skies.
Snowpack
We found 8 to 10 inches of new snow that fell over the last three days. Snow was mostly F to 4F at lower elevations trending to 1F near and above the treeline. Fresh slabs were generally soft but produced cracking below our skis in drifts around a foot deep. We observed easy propagating failures below the wind-drifted snow, but those same slabs were reluctant to fail from ski pressure on steeper, small test slopes. Similar to other areas in the San Juan Mountains, persistent weak layers of concern are just over a meter deep and show initial signs of rounding. Despite this, we continue to observe propagating failures below the holiday slab in faceted grains, albeit with more force. Once failure was initiated, the block slid into the snowpit with excitement. Storm/ density layers in the upper snowpack continue to produce non-propagating failures and beg the question of how big of a load will it take for those layers to produce avalanches. We did not observe failures in a thin layer of near-surface facets below an easily identifiable rain/ temperature crust that formed around the new year. No shooting cracks or audible collapses as the mountains remain quiet while our Persistent Slab problem becomes more stubborn with each passing day. If choosing to step into steeper slopes, do so with a level of trepidation as the potential size of a slide you can trigger remains larger versus small.