My partner and I triggered this slide from the ridgetop. We heard a huge collapse and watched cracks propagate alonfg the ridge before avalanching the cornices and slope below. The slide propagated up and down the ridge about 1,000 feet. The crown was 3-5 feet deep and was a hard slab that pulled out trees. It was a north to northeast aspect at 9,500 feet. It ran about 600 feet vertical . Check out the video of the aftermath. Photo: GNFAC
11-12
This photo was taken from the Wilderness Boundary looking into the head of Beaver Creek. This continuous crown line was very, very long and likely broke sometime this morning. Photo: GNFAC
Forecast link: GNFAC Avalanche Forecast for Tue Mar 20, 2012
This climax avalanche on the east face of Ernest Miller Ridge ran full path. This likely released early Sunday (3/18). Ernie Miller is located to the west of Bacon Rind in the southern Madison Range. Photo: D. Wykoff
Forecast link: GNFAC Avalanche Forecast for Tue Mar 20, 2012
GNFAC Avalanche Advisory for Mon Mar 19, 2012
Snowpack and Avalanche Discussion
The southern Gallatin Range, southern Madison Range and the Lionhead area near West Yellowstone:
This avalanche was on the west side of the Bridger Range on a path called Saint Lawrence. It broke at the ground and ran over 1,000 vertical feet. Photo: P. Carse
Forecast link: GNFAC Avalanche Advisory for Mon Mar 19, 2012
This avalanche happened last night (Sat, 3/17). Starting point in upper left of red line which denotes the crown. It broke at the ground. Photo: L. Watson
The debris ran almost full track. It measures over 1,000 feet vertical. Photo: L. Watson
This slide occurred on the trail leading to Two Top outside of West Yellowstone. Over two feet of heavy snow has fallen in this area over the past week producing widespread natural and human triggered avalanches. Photo Jim Norlander
GNFAC Avalanche Forecast for Sun Mar 18, 2012
Snowpack and Avalanche Discussion
The southern Gallatin and southern Madison Ranges and the Lionhead area near West Yellowstone:
The snowpack is complicated, but the avalanche problem is easy. Weak, faceted layers buried deep in the pack are reacting to the two+ feet of heavy, dense snow that has fallen over the past week. This new load is pushing many slopes past their breaking point, which was evident during our ride into the Lionhead area yesterday (photo).
Two distinct weak layers exist in the snowpack near Lionhead. Both layers are fully capable of producing avalanches. Photo GNFAC