This pit was dug in the crown of an avalanche that likely occurred 3-4 days ago. A heavy wind load deposited on a well defined sun crust made this slope unstable. It is unclear if this slide was human triggered or a natural.
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GNFAC Avalanche Advisory for Thu Feb 10, 2011
Snowpack and Avalanche Discussion
The Bridger and northern Gallatin Ranges:
In the past 48 hours strong winds blew the new snow (30 inches from the weekend) onto W aspects then back to E aspects by yesterday afternoon. This dramatic event was evident from Bozeman where we could see cornices in the Bridger Range facing town in the morning. By afternoon the same locations had been scoured to bare rock and the cornices were gone. This redistribution of snow is a red flag and a warning sign by itself.
GNFAC Avalanche Forecast for Wed Feb 9, 2011
Snowpack and Avalanche Discussion
The Bridger and northern Gallatin Ranges:
This natural avalanche occurred in Hyalite Canyon on an E aspect around 9500 ft. It was about 3 ft deep and 350 ft wide. The debris stopped on a slight bench where the slope angle lessened. Another slide was observed nearby on a S aspect. Photo: B. Carpenter
This slope collapsed and cracked as we approached. It failed on facets that formed last week. This week layer is responsible for the avalanche warning in the Bridgers, northern Gallatins and Cooke City area. It's widespread, but in the southern Madison it has not been loaded enough to heighten the avalanche danger. Photo: GNFAC
This natural slide likley occurred during the storm on Feb 7th. Natural avalanche activity is bulls eye information the snowpack is unstable. Photo GNFAC
Forecast link: GNFAC Avalanche Forecast for Wed Feb 9, 2011
GNFAC Avalanche Advisory for Tue Feb 8, 2011
Snowpack and Avalanche Discussion
The Bridger and northern Gallatin Ranges, the mountains around Cooke City and the Washburn Range:
Frazier Avalanche
Two separate parties of skiers triggered avalanches near Frazier Lake in the northern Bridger Range.
GNFAC Avalanche Forecast for Mon Feb 7, 2011
Snowpack and Avalanche Discussion
The Bridger Range, the northern Madison and northern Gallatin Ranges, the mountains around Cooke City and the Washburn Range:
Yesterday, a skier was caught and injured in a slide near Frasier Lake in the northern Bridgers. The slide broke 18” deep and failed on the skiers first turn, resulting in a long and harrowing ride. This incident resulted in a broken femur. A second group triggered another side in the same area, but fortunately no one was caught. Read a more detailed report at the end of the advisory.