23-24

Skier triggered, caught and injured near Mt Blackmore

Mt Blackmore
Northern Gallatin
Code
SS-ASu-R3-D2-O
Elevation
9000
Aspect
NE
Latitude
45.44440
Longitude
-111.00400
Notes

Two skiers were ascending a northeast-facing avalanche path on the northernmost ridgeline of Mount Blackmore around 1 PM when they triggered a large, dry slab avalanche that failed 3 feet deep, 150 feet wide, and ran 500 feet vertical. Debris piled up 4-8 feet deep. The avalanche failed on weak, faceted snow near the base of the snowpack. 

As the group was about halfway up the avalanche path, they saw a small slide initiate to their right and then they heard a loud boom as the rest of the slope collapsed 250 feet above them. The skier lower on the path sprinted to the left into the trees to avoid getting caught. The second skier was 30 higher on the slope. He attempted to run off the slope but was unable to avoid getting captured. He was carried to the bottom of the avalanche path, got submerged in the snow, but thankfully came to rest on the surface. His partner initiated a beacon search and called his name, quickly finding him on top of the avalanche debris. The skier sustained significant injuries. They called 911 and Gallatin Country Sheriff Search and Rescue initiated a response with the Helicopter team. The two skiers worked to address injuries while awaiting rescue. GCSAR inserted a team with a helicopter that provided medical treatment and both the injured and uninjured skiers. The GNFAC was on scene to evaluate the scene for hazards to the rescue team. 

Number of slides
1
Number caught
1
Number buried
0
Number killed
0
Avalanche Type
Soft slab avalanche
Trigger
Skier
Trigger Modifier
u-An unintentional release
R size
3
D size
2
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
36.0 inches
Vertical Fall
500ft
Slab Width
150.00ft
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Two skiers were ascending a northeast-facing avalanche path on the northernmost ridgeline of Mount Blackmore around 1 PM when they triggered a large, dry slab avalanche that failed 3 feet deep, 150 feet wide, and ran 500 feet vertical. Debris piled up 4-8 feet deep and broke a number of mature trees. Photo: GNFAC

Northern Gallatin, 2024-03-19

Two skiers were ascending a northeast-facing avalanche path on the northernmost ridgeline of Mount Blackmore around 1 PM when they triggered a large, dry slab avalanche that failed 3 feet deep, 150 feet wide, and ran 500 feet vertical. Debris piled up 4-8 feet deep. This photo captures the first area to avalanche on the climber's right side of the path. Photo: GNFAC

Northern Gallatin, 2024-03-19

Two skiers were ascending a northeast-facing avalanche path on the northernmost ridgeline of Mount Blackmore around 1 PM when they triggered a large, dry slab avalanche that failed 3 feet deep, 150 feet wide, and ran 500 feet vertical. Debris piled up 4-8 feet deep. One skier was carried to the bottom left of the runout zone. Photo: GNFAC

Northern Gallatin, 2024-03-19

Two skiers were ascending a northeast-facing avalanche path on the northernmost ridgeline of Mount Blackmore around 1 PM when they triggered a large, dry slab avalanche that failed 3 feet deep, 150 feet wide, and ran 500 feet vertical. Debris piled up 4-8 feet deep. One skier was carried to the bottom left of the runout zone. Photo: GNFAC

Northern Gallatin, 2024-03-19

Two skiers were ascending a northeast-facing avalanche path on the northernmost ridgeline of Mount Blackmore around 1 PM when they triggered a large, dry slab avalanche that failed 3 feet deep, 150 feet wide, and ran 500 feet vertical. Debris piled up 4-8 feet deep. Photo: GNFAC

Northern Gallatin, 2024-03-19

Deep Slab Avalanche near Mt Blackmore

Date
Activity
Skiing

Two skiers were ascending a northeast-facing avalanche path on the northernmost ridgeline of Mount Blackmore around 1 PM when they triggered a large, dry slab avalanche that failed 3 feet deep, 150 feet wide, and ran 500 feet vertical. Debris piled up 4-8 feet deep. The avalanche failed on weak, faceted snow near the base of the snowpack. 

As the group was about halfway up the avalanche path, they saw a small slide initiate to their right and then they heard a loud boom as the rest of the slope collapsed 250 feet above them. The skier lower on the path sprinted to the left into the trees to avoid getting caught. The second skier was 30 higher on the slope. He attempted to run off the slope but was unable to avoid getting captured. He was carried to the bottom of the avalanche path, got submerged in the snow, but thankfully came to rest on the surface. His partner initiated a beacon search and called his name, quickly finding him on top of the avalanche debris. The skier sustained significant injuries. They called 911 and Gallatin Country Sheriff Search and Rescue initiated a response with the Helicopter team. The two skiers worked to address injuries while awaiting rescue. GCSAR inserted a team with a helicopter that provided medical treatment and transported both the injured and uninjured skiers. The GNFAC was on scene to evaluate the scene for hazards to the rescue team. 

Region
Northern Gallatin
Location (from list)
Mt Blackmore
Observer Name
Dave Zinn

My partner and I were approaching Responsible FamilyMan via Avalanche Gulch early yesterday morning (3/18), and once we broke through the trees into the runout zone, we stumbled across a pretty large wet avalanche debris field. The debris terminated within ~50 yards of the max runout zone. Photo: R. Parsons

Northern Gallatin, 2024-03-19