On February 19, 2022, three snowmobilers and two snow bikers were in Sheep Creek on the south face of Miller Mountain north of Cooke City. The two snow bikers were high on the slope when one stopped on a small ridge while the other climbed higher and triggered a large avalanche. The avalanche carried him down through a gully and over a cliff where he was partially buried near the toe of the debris. His arm and airbag were visible and his head was 1 foot under the surface. Resuscitation efforts were unsuccessful. The avalanche was 800 feet wide, averaged 2 feet deep (estimated) and ran 1200 vertical feet. The avalanche likely broke on facets and depth hoar at the bottom of the snowpack in an area that was thinly covered and recently wind-loaded. The debris was up to 15 feet deep. The avalanche is classified SS-AMu-R3-D3-O.
Sheep Creek
Cooke City
Code
SS-AMu-R3-D3-O
Elevation
9800
Aspect
S
Latitude
45.03900
Longitude
-109.98100
Notes
Number caught
1
Number buried
1
Number killed
1
Avalanche Type
Soft slab avalanche
Trigger
Snowmobile
Trigger Modifier
u-An unintentional release
R size
3
D size
3
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
24.0 inches
Vertical Fall
1200ft
Slab Width
800.00ft
Attached Videos
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year