The southern Madison and southern Gallatin Ranges, Lionhead area near West Yellowstone and mountains around Cooke City:
The mountains near West Yellowstone have a snowpack structure similar to a lead safe balancing precariously on stacked wine glasses. This fragile balance will continue as long as a major disruption i.e...new snow, wind loading or a skier/snowmobiler does not facilitate additional stress.
The southern Madison and southern Gallatin Ranges, the Lionhead area near West Yellowstone, and the mountains around Cooke City:
The weakest and most unstable snowpack exists near West Yellowstone. On all slopes, the bottom half of the snowpack contains weak facets which will be evident when you step off your sled or out of your skis and sink to the ground. Unfortunately this situation will not change any time soon. Without any new snow, natural avalanche activity has subsided, but human triggered avalanches remain likely.
This natural avalanche occurred recently just south of Silver Gate on a ENE facing slope around 9000ft. It appears to be wind loaded from the left side, but it propagated of a wide area indicating the existence of a widespread, persistent weak layer. Photo: B. Zavora
The southern Madison and southern Gallatin Ranges, and the Lionhead area near West Yellowstone:
Southerly aspects have a facet crust combo beneath the new snow, which is producing unstable results in stability tests. It's worth digging down to look for this layer if you're skiing on sun affected slopes. Photo: GNFAC
The southern Madison and southern Gallatin Ranges, Lionhead area near West Yellowstone and mountains around Cooke City:
