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GNFAC Avalanche Forecast for Wed Dec 7, 2011
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone and mountains around Cooke City:
A skier noted significant cracking above 9,500 feet on Mt. Republic yesterday. This hard slab of windblown snow cracked 30+ feet on a <30 degree slope. Cracking is Bull's-eye data that the snow is unstable. Photo: Beau Fredlund
Forecast link: GNFAC Avalanche Forecast for Wed Dec 7, 2011
This three foot deep snowpack was breaking near the ground on facets. ECTP22,Q1 was our test score. The pit was at 9,330 feet on a southeast facnig slope. We were not excited to find the weak snow propagating fractures and we stuck to terrain that was not exposed to avalanches. Photo: GNFAC
Mark Staples checked out the weather station today which has been broken since it got hit with 100 mph winds over a month ago. It'll require another trip later in the season to repair. Situated at a little over 10,000 feet near Flanders peak we got a great view of the surrounding mountains. The Bridger Range is in the far distance. Photo: GNFAC
GNFAC Avalanche Advisory for Mon Dec 5, 2011
Snowpack and Avalanche Discussion
The northern Gallatin Range and mountains around Cooke City:
A recent, natural slide on a wind-loaded, south-southwest facing slope on Sheep Mountain outside Cooke City. Photo: B. Zavora
Photo of a natural slab avalanche that ran in the last 24 hrs outside Cooke City up Sheep Creek. It was a northeasterly aspect around 9400’ and as you can see it’s thin- maybe a foot deep, and around 70’ wide. A couple of other natural sluffs were noted, N and S aspects, short running, new snow, from the last 24 hrs as well. Photo: Beau Fredlund
This east facing slope at 8100 feet is comprised of facets. Nine days ago it was stronger, but the cold temperatures turned the snow crystals into large grains of unbonded snow. Here is a snowpit of this picture (http://www.mtavalanche.com/images/11/ski-hill-lionhead-0?size=_original) and here is a video of Eric Knoff explaining the snow structure (http://www.youtube.com/watch?v=dDwWL8vMDyY). Photo GNFAC.
Forecast link: GNFAC Avalanche Advisory for Mon Dec 5, 2011