Deep Slab Avalanche in Blackmore Basin

Deep Slab Avalanche in Blackmore Basin

Date
Activity
Snowboarding

My partner and I observed a deep slab avalanche in Blackmore Basin that appeared to break on the depth hoar near the bottom of the snowpack. It was on a wind loaded NE facing slope at approx. 9,500 and looked to break on a slope in the 35-40 degree range. The crown was about 8'-10' deep and 200' wide. It broke to the ground and ripped out several small trees.
As soon as we saw it, we came over a small ridge to see another skier near the debris. According to him it was triggered remotely by one of the two skiers on the coming down on the lookers right of the slide (in the second photo). We confirmed that a beacon search was done to make sure no one was buried.
Earlier in the day we dug a pit near the summer on an east facing slope and got no results. After seeing this we avoided avalanche terrain and took a low angle route down. We were glad no one was buried and found some great snow!

Region
Northern Gallatin
Location (from list)
Mt Blackmore
Observer Name
JR Mooney