Snowmobile Triggered Avalanche in Black Canyon

Island Park
Code
SS-AMu-R3-D2-O
Latitude
44.54760
Longitude
-111.23900
Notes

From interaction at the gas station:

“We were riding out from Island Park. We saw dramatic, collapses, and shooting cracks. I side-hilled a small slope and triggered it 1.5 to 2 feet deep. I have never seen such unstable snow.”

The avalanche likely failed on a layer of surface hoar widespread in the Lionhead and Island Park areas. The avalanche buried part of the groomed road that crosses below this slope. 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft 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
18.0 inches
Vertical Fall
50ft
Slab Width
100.00ft
Weak Layer Grain type
Surface Hoar
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year