Southern San Juan
SnowpackChris Bilbrey · Feb 23, 2024 · Southern San Juan
Weather
Hint of early-spring today in the Wolf Creek Pass area. A light breeze at upper elevations kept things in check under sunny skies, and a few high, thin clouds. Southerly-facing snow surfaces got wet and mushy below about 10,000 feet from today's warm-up.
Snowpack
Snow coverage and depths are deeper near and below treeline, while more variability exists across alpine slopes. Despite near average snowfall so far this season, we still encountered shallow areas near ridgelines and around steep convexities. In these places, the main slab body is not as thick or stout, and we encountered trap-door conditions where weak snow layers are closer to the surface. Like the old say..."no stones left unturned"...elevated winds this week did all they could to touch as many slopes as possible. We found mixed-bag surface conditions ranging from Sastrugi to Styrofoam to textured facets to wind-board to sun crust near and above treeline. We even found wind-stiffened surfaces as low as 11,000 feet in spots. The hard snow surfaces (wind-board or crust) ranged 4 to 5 cm thick on average, with 10 to 15 cm of F to 4F facets below. This stiff-over-soft setup produced sudden planar results with 3 and 4 taps on a southeast aspects, and progressive collapse results with 10 taps on a west-southwest aspect. Northerly aspects harbor the same weak facets below a hard wind-board, and in isolated spots, the wind-board is starting to break down and facet on top. Crust at lower elevations are thicker and more robust across slopes, and lack the same degree of faceting as higher up. These slick surfaces became more breakable the higher we climbed. The early-February faceted crust interface on east through south to southwest was stubborn to fail in snowpack tests, but did so with moderate to hard force and resistant planar failures. The same lineage interface on northerly aspects was less obvious when probing around, and has more homgenous hardness layers in the top 2 to 3 feet from the surface. We did not perform snowpack tests on the 2/2 or 2/6 interface on northerly aspects.