A rider saw natural avalanche activity and also remotely triggered two slides from flat terrain on Friday and Saturday. 1-2 feet of new snow has made the southern mountains extremely unstable. Photo: Dan Nelson
This avalanche was triggered from a skier ascending an adjacent ridge. The slide was on the ESE of Yellow Mountain on a 34 degree slope. The crown was 18 inches deep and ran on facets putting debris 700-1000 feet down the slope. Photo: Mason Young
The southern Madison and southern Gallatin Ranges, the Lionhead Area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
The Madison and southern Gallatin Ranges, the Lionhead Area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
The Madison and southern Gallatin Ranges, the Lionhead Area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
The Madison and southern Gallatin Ranges, the Lionhead Area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
This snowmobiler triggered slide is located in Sheep Creek outside Cooke City. It was southeast facing, 9400 feet, 100 feet wide and 2-4 feet deep. Current human triggering indicate persistent instabilities in this area. Photo: Beau Fredlund
The Madison and southern Gallatin Ranges, the Lionhead Area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
This slope had 10-20 tracks on it prior to the avalanche. A rider triggered it on Dec 27. He was caught, but not buried. A layer of sugary snow underlies a dense, supportable slab of snow. Riders are able to easily climb slopes, but there are spots where the weak snow can not hold both the slab and rider.
