Witnessed a slide last week on a 40 degree fairly heavily treed NE facing slope at 6800 feet that slid on the crust/hoar frost layer about 14-16” down. Skier triggered, (second skier on the line) took him for a ride but he was able to grab a tree and self arrest as the slide passed under him. It continued to run another 150 yards or so down slope, again through fairly tight trees. About 30 yards wide at the deposition zone. In the mountains Northwest of Whitefish. Biggest fracture and slide I have ever witnessed in tightly spaced trees in 30 years of backcountry skiing. Definitely spooky out there. ...We aggressively ski cut the line directly above prior, group went one at a time with eyes on, all remaining in group skied the slid out areas of the path on the old freeze layer that the slide broke on so as not to trigger anything additional. Want to emphasize have never seen a slide like that in that tight of trees, will be sticking to low angle and resort skiing until that layer heals.
See quick obs. Reported 2/16 but occurred week prior. Skier shaken but not injured.
