This avalanche likely released over the weekend after Sunday's storm. It may have been skier triggered. It was on the Throne (aka. First Flatiron) in the northern Bridgers.
08-09
GNFAC Avalanche Forecast for Mon Mar 9, 2009
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone:
The simple part of today’s advisory is that significant snowfall combined with significant weak layers means avalanches are very likely today. Since snowfall began in the middle of last week, numerous natural and human triggered avalanches have occurred and more will occur today. Much of this activity has occurred in the Bridger Range. When the sun appeared on Saturday, many natural avalanches were observed and photos can be seen at: http://www.mtavalanche.com/photos/photos.php
GNFAC Avalanche Forecast for Sun Mar 8, 2009
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone:
GNFAC Avalanche Advisory for Sat Mar 7, 2009
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
This natural avalanche occured just south of Saddle Peak in the Bridger Range Friday night/Saturday morning. Notice the trees and rocks this avalanche ran through. The debris hit a bench and piled up very deeply. Photo: T Saracelli
Forecast link: GNFAC Avalanche Forecast for Sun Mar 8, 2009
One of these natural avalanches occured sometime Friday and one occured later that night or early Saturday morning. The slide on right ran nearly 1500 ft. Photo: T Saracelli
Forecast link: GNFAC Avalanche Forecast for Sun Mar 8, 2009
The Moonlight Basin Ski Patrol triggered this avalanche on north facing, wind loaded terrain with explosives. As the slide ran downhill it triggered a larger avalanche that ran on facets near the gound breaking 1-3 meters deep. Photo: MBSP
Forecast link: GNFAC Avalanche Forecast for Sun Mar 8, 2009
GNFAC Avalanche Forecast for Thu Mar 5, 2009
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
This avalanche released when someone walked onto a cornice that broke. The person and cornice triggered the slide. It ran approx 2'deep, 75' wide and 100' vertical.
Forecast link: GNFAC Avalanche Forecast for Thu Mar 5, 2009
GNFAC Avalanche Forecast for Wed Mar 4, 2009
Snowpack and Avalanche Discussion
The Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
The mountains outside West Yellowstone and Cooke City have seen 6-10 inches of snow, but that’s not the whole story. As forecasters we’re interested in how much weight was added to the snowpack. The snow that fell was very, very dense, and in some cases it rained before the snow fell. The remote SNOTEL sites outside West Yellowstone show 1.0 inch of water fell since 3 a.m. yesterday, while 1.3 inches fell near Cooke City. This is rapid loading and it’s still snowing.