Northern San Juan
AvalancheKrista Beyer · Jan 19, 2025 · Northern San Juan
Weather
-18 degrees at 9am in Silverton. Wind speeds averaged 18 mph throughout the day primarily west. Yesterday's winds were primarily north. 24 hour peak gust was 47 mph. Daytime high at 11,000 ft was 7 degrees.
Snowpack
The goal of today was to see what the north and west winds did to the alpine. 2-3 inches of new low-density snow arrived with Saturday's arctic airmass. North, northwest, and west winds drifted snow at ridgeline. Recently wind drifted snow was isolated to ridges and concave dished features. Wind drifted snow was soft, and stubborn to ski pressure. A pit on a southeast near treeline slope revealed crust-facet layering in the upper snowpack. I observed moderate and hard non-propagating results on these facet layers. A Persistent Slab avalanche problem may still exist on some southeast slopes, but it would be in isolated areas and increasingly challenging to impact. The recent north winds seem to have done a better job of pressing surfaces and stripping snow in the alpine than drifting and loading slopes. Above treeline elevation bands have seen the most impact from the wind. The near treeline elevation band maintains a softer and deeper snowpack than the more exposed wind-impacted above treeline slopes. Due to this deeper snowpack and connected cohesive slabs formed by recent snowfall and winds, near treeline remains the most dangerous elevation band for triggering a large avalanche.
Avalanche
Minor cracking and collapsing was observed below treeline isolated to road cuts, depressions, and flat terrain. Small surface sluffing on steep rolls below treeline. This is likely due to faceting and loss of cohesion in the surface snow.