Skier triggered avalanche on Mt. Blackmore

Mt Blackmore
Northern Gallatin
Code
SS-ASu-R2-D1.5-I
Aspect
NE
Latitude
45.44550
Longitude
-111.00400
Notes

From an email:

"I’d like to report an avalanche incident that occurred today, 3/6, around 2 PM on the NE face of Mt. Blackmore in the Hyalite Canyon area. On the approach, I dug a pit at 9400’ and found a very stable and deep snowpack, with a somewhat definite weak layer in between high and medium density snow about 8” deep. The layer did not slide or propagate in an extended column pit test, so my partner and I decided do ski the direct line from the summit. I skied first, making a ski cut just below the ridge line that did not result in any sloughing. I skied the line without mishap. My partner followed, traversing onto a shallow, steep pocket, releasing the avalanche. It propagated down and out in both directions, resulting in a v-shaped crown about 100’ across and 8-12” deep. The slide ran from around 9800’ to 9400’. My partner was not caught and was able to traverse out and ski down safely."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Skier
Trigger Modifier
u-An unintentional release
R size
2
D size
1.5
Bed Surface
I - Interface between new and old snow
Problem Type
Persistent Weak Layer
Slab Thickness
10.0 inches
Vertical Fall
400ft
Slab Width
100.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche