20-21

Natural, North Face Alex Lowe

Alex Lowe Peak
Northern Gallatin
Code
HS-N-R3-D2.5-O
Aspect
N
Latitude
45.42720
Longitude
-111.01400
Notes

From Obs: "One large avalanche observed, on the path adjacent to the N Couloir on Alex Lowe. More or less went full path, I would estimate 2m max crown depth. HS-N-R4/D2.5-O. A large cornice fell on the NF of Blackmore with no slab results. Observed several size 1 slabs that failed within new snow during the day on N aspects."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
R size
3
D size
2.5
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
200.0 centimeters
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

From Obs 2/9/21: "Up/down the SE Ridge of Blackmore today. No cracking/collapsing observed. One large avalanche observed, on the path adjacent to the N Couloir on Alex Lowe. More or less went full path, I would estimate 2m max crown depth. HS-N-R4/D2.5-O. Observed several size 1 slabs that failed within new snow during the day on N aspects." Photo: S. Hennessey

Northern Gallatin, 2021-02-09

Natural avalanches along Bridger Ridge

Bridger Peak
Bridger Range
Code
HS-N-R3-D2.5-O
Elevation
8600
Aspect
NE
Latitude
45.77010
Longitude
-110.94000
Notes

Seen on 2/9/21: Many natural avalanche crowns along the Bridger Ridge that ran during the storm from 2/4-2/8, likely between 2/5-2/7. Across all of Bridger Peak, some on Baldy Peak, Many through The Pinnacles, Argentina Bowl and Saddle.

Number of slides
5
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
R size
3
D size
2.5
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
30.0 inches
Vertical Fall
1700ft
Slab Width
1000.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year

Natural Avalanches on Cedar mountain

Cedar Mtn.
Northern Madison
Code
SS-N-R2-D3-O
Elevation
9600
Aspect Range
E-N
Latitude
45.22680
Longitude
-111.51200
Notes

I observed 4 avalanches that broke at a variety of aspects and elevations on Cedar Mountain during the tail end of the storm, likely Feb. 5-8, 2021

Number of slides
4
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
2
D size
3
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year

Many Natural Avalanches - Muddy Creek

Buck Ridge
Northern Madison
Code
SS-N-R2-D2
Elevation
8400
Aspect Range
S-E
Latitude
45.17190
Longitude
-111.38000
Notes

I counted 11 natural avalanches in Muddy Creek that failed during the tail end of the storm. They mostly appear to be storm slab avalanches, but some may have broken deeper. 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year