Southern San Juan
SnowpackChris Bilbrey · Jan 10, 2023 · Southern San Juan
Weather
A mixture of overcast, obscured, and broken skies along with moments of S-1 snowfall and graupel. Generally mild temperatures and light winds along ridgetops.
Snowpack
We traveled on all aspects below the treeline and found snow depths between 100 and 170 cm. The holiday slab is deeper and a bit stiffer closer to the ridgetops - even though those ridges are heavily treed. The same slab is slightly shallower in thicker old-growth forests and a couple of hundred feet downslope. Drought layer facets on north and east-facing slopes were around 100 to 125 cm below the surface with a dense slab stacked above. We did not observe propagating failures in weak, older snow at the bottom of the snowpack but we did observe repeatable resistant planar failures in a storm/ density layer change and a very thin layer of NSFs that developed in between January snowfall. While a concerning basal structure was found throughout our travels, the slab/ weak layer combination appears to have become more stubborn as the overlying slab settles and compresses weaker snow below. This transition is making it more difficult to impact weaker snow below, but still, shallow areas still have the recipe to fail from the added weight of a rider or more likely from a machine.