Northern San Juan
AvalancheAnonymous · Feb 18, 2024 · Northern San Juan
Weather
Heavy snowfall at times (S1-S2) that tapered off throughout the day. Low visibility, with obscured skies until the late afternoon. Winds persisted out of the WSW 10-15 G30. Temperatures in the mid-20s.
Snowpack
The snowpack varied throughout where we traveled and across aspects/elevation bands, but generally was quite shallow. On more solar aspects and in the dark timber, some places were only 50 cm deep, ranging to ~120-150+ cms where the avalanche was triggered. On west aspects, where the avalanche was triggered, there was approximately 4 inches of fresh snow over a weak snowpack to the ground, with the slab not being harder than 4 finger in most locations when observed with various hasty observations with ski poles and hands. Likely depth hoar at the ground.
Avalanche
On our second lap, we were descending a west-facing ridge, down from 11,700' on the west side of Kendall Mountain. The terrain alternated between very dense trees and open glades, and the group skied short pitches, careful to not stop below steeper terrain, and regrouping in lower-angle areas that provided line of sight when possible. We were successfully staying on-route, which became more complicated and had thinner margins through the middle. We all stopped and regrouped before entering an opening in the trees, which led to an admittedly enticing, steep, nicely gladed area. We had previously discussed wanting to avoid this terrain. To control himself from skiing the open powder below, Skier 1 verbalized that he was only going to take one turn into the open and head immediately back into the trees, and we all agreed. Skier 1 descended the edge of the dark timber next to the meadow, and as he cut back towards the trees, the steep part of the slope above and to his left cracked, shattered, and began to avalanche, entraining all of the snow on steeper terrain to the ground, running through the trees. The slope was W-facing, 35°, 10,800'. We immediately yelled "avalanche!" and in a few moments could see Skier 1 through the thick trees below us. Skier 1 yelled to the group, confirming he was in a location out of the path. The avalanche continued through the trees approximately 1,000' (700' vertical) to CR 33 below. We carefully continued our descent avoiding any open areas and made our way back to the road as delicately as possible, continuing as before in short pitches. From there we skied back down to Silverton and later retrieved the snowmobiles, where we assessed the debris from the bottom. It had continued to entrain snow on the way down through steep terrain, and crossed the road. The debris pile was 6' deep or more in places.