Avalanche: Six Mile Canyon

Snowmobiler triggered this slide near the fracture line and was caught and carried but was able to regain enough control of his sled to maneuver out of the slide before it stopped. It broke deep into older weak snow.

We attempted to visit the site on Saturday but heavy snowfall, poor visibility and additional avalanche concerns hampered our goal. We did obtain some good info though. This was a very curious avalanche.

The slide was triggered Friday. That day, Travis climbed up the bed surface to the fracture line. He reports it was chest high, about 5' deep. The slide broke to the ground. It contained about 4 feet of strong snow with around a foot of facets at the ground.

Near the debris pile, we probed and found a total of 7 to 8 feet of snow. The snowpack structure was much different (image below) than what Travis found at the fracture line. It was much deeper and much stronger near the debris pile. This doesn't make sense because, given the leeward facing wind loaded slope, the snowpack should've been deeper at the fracture line than in the flats down below. This leads me to believe that the avalanche path already released earlier this season, leaving a shallower snowpack and thus, a weaker snowpack. This has been a theme in regions to our north this winter but this is the first case that I believe this to be true here on the Skyline.