Natural avalanche north of Lulu Pass, Cooke City

Lulu Pass
Cooke City
Code
HS-NC-R4-D2.5-O
Elevation
9750
Aspect
NE
Latitude
45.08130
Longitude
-109.96000
Notes

This avalanche was a hard slab of wind-loaded snow on a very steep (50 degree) slope with monster cornices above. NE facing, 9700’, and likely ran Wed or Thursday (1/15 or 1/16) deduced from snow on debris. It was cornice triggered and ran on the facets near the ground, propagated 300’ wide, 150’ vertical and 3-6’ deep.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Cornice fall
R size
4
D size
2.5
Bed Surface
O - Old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
48.0 inches
Vertical Fall
150ft
Slab Width
300.00ft
Weak Layer Grain type
Depth Hoar
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year