Southern San Juan

Avalanche

Chris Bilbrey · Jan 17, 2019 · Southern San Juan

Weather

Warm and sunny to start out with light southwest winds below treeline. Once we gained the ridge, winds speeds increased to moderate with strong gusts noted by 2 pm. Clouds built throughout the day and were overcast by 3 pm. Snowfall started out on higher peaks around 3:30 pm.

Snowpack

Recent storm snow has settled and consolidated quickly and made for easier skinning today. Did not observe any cracking or collapses on multiple aspect. Using small, non-consequential test slopes we did not observe any signs of unstable storm snow. Storm slabs appeared to be borderline stubborn to unreactive in the terrain we traveled. Lots of natural activity observed from recent storm cycle with most avalanches occurring on steep convexities or below cliff bands and failing on buried weak layers in top meter of snowpack. Up to 5 mm surface hoar formed on snow surface in wind-sheltered areas facing east and north. Total snow depths varied from 1 m up to 2 m (northerly aspects). Despite deeper snow depths and reduced signs of instability, weaker snow still persist on many slopes. Slabs built from late December and early January added a significant load and the snowpack still seems to be finding an equilibrium.

Avalanche

We observed natural avalanches on west, northwest, north, northeast, and east-facing slopes in all elevation bands. Most widespread activity seen in near and above treeline terrain.