Northern San Juan
AvalancheChris Dickson · Nov 27, 2024 · Northern San Juan
Weather
Calm winds, with sunny skies that turned cloudy and snowy around mid-morning. Cold with temperatures in the 20* F range.
Snowpack
The new 20 inch slab atop our snowpack is behaving like a persistent slab avalanche problem. Reactivity was most touchy on slopes that tilted towards the north, or in shady pockets of trees. These areas harbored very weak faceted surfaces prior to the storm. There was less reactivity on easterly slopes, which featured a melt-freeze crust under the storm snow.
Avalanche
Above 10,500', we found it became very easy to trigger avalanches. As I walked along a flat bench with a steep slope below me, I heard an loud whumph, felt the snow underneath me collapse, and then an avalanche released about 200 feet away on the steep northeasterly slope below me. The avalanche featured wide propagation along a convexity. The same collapse produce large cracks on adjacent slopes at least 200 feet away. Other backcountry travelers in the area remotely-triggered two more avalanches from a flat ridge as they put in the skintrack. These avalanches released on steep north-facing slopes below treeline. The sensitivity of the slab is best described as "touchy" in this area.