Snowmobiler triggered hard slab avalanche Sheep Mtn.

Sheep Mountain
Cooke City
Code
HS-AMu-R3-D2-O
Elevation
10000
Aspect
W
Latitude
45.07220
Longitude
-109.92800
Notes

...we rode over the saddle between Sheep and Scotch Bonnet and saw an avalanche that appeared very recent, and likely triggered by a snowmobiler. It was on a west facing slope at 10,000', and was a hard slab 1-4 feet deep and 150' wide, ran about 200' vertical. AMu-HS-R3-D2-O. This was a clear sign that weak layers exist, especially where the snowpack is relatively shallower, and recent snow has been drifted into thick slabs that are unstable over this weak snow.

 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Snowmobile
Trigger Modifier
u-An unintentional release
R size
3
D size
2
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
42.0 inches
Vertical Fall
200ft
Slab Width
150.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year