Northern Gallatin

On the descent, I intentionally triggered a small wind pocket in one of the chutes in the cliffs near the trail at 8700 ft. I included a video. It was D1 and about 5 inches deep at the crown. I think just a good reminder that even in the trees, the tops of those chutes get wind loaded and can definitely slide. Photo: H. Darby

Northern Gallatin, 2022-11-28

Saw a group of skiers trigger a small wind slab avalanche on an eastern aspect at around 8,300' in the main fork of Hyalite in "Candy Land" just south of the climb Big League Chew at 2:00pm on Saturday (11/26). Crown looked to be around 2" to 1' and 90' wide. The slide ran maybe 100'. No skiers were caught. Photo: Anon

Northern Gallatin, 2022-11-28

Saw a group of skiers trigger a small wind slab avalanche on an eastern aspect at around 8,300' in the main fork of Hyalite in "Candy Land" just south of the climb Big League Chew at 2:00pm on Saturday (11/26). Crown looked to be around 2" to 1' and 90' wide. The slide ran maybe 100'. No skiers were caught. Photo: Anon.

Northern Gallatin, 2022-11-28

Skier triggered wind slab east aspect Hyalite

Hyalite - main fork
Northern Gallatin
Code
SS-AS-R1-D1-O
Elevation
8300
Aspect
E
Latitude
45.44720
Longitude
-110.96200
Notes

Saw a group of skiers trigger a small wind slab avalanche on an eastern aspect at around 8,300' in the main fork of Hyalite in "Candy Land" just south of the climb Big League Chew at 2:00pm on Saturday (11/26). Crown looked to be around 2" to 1' and 90' wide. The slide ran maybe 100'. No skiers were caught. It was triggered as the first skier traversed out onto the intended ski line from the trees which they skinned up. The fracture extended from the tips of the first skiers skis and ran across the slope and underneath a small cliff band. The group skied out on a slightly lower angle slope adjacent to the slide. My group watched from below an adjacent ski run approximately 300 yards away as the slide happened. We had dug a pit on a similar aspect in the area approximately 30 minutes before the slide and found 85cm of snow with a weak layer at 42-45cm which failed CTs but we couldn't get propagation. (CT22, ECTN21). It looked like this was probably the layer that failed in this slide.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Skier
R size
1
D size
1
Bed Surface
O - Old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
6.0 inches
Vertical Fall
100ft
Slab Width
90.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Small wind slab avalanche east aspect Hyalite

Date
Activity
Skiing

Saw a group of skiers trigger a small wind slab avalanche on an eastern aspect at around 8,300' in the main fork of Hyalite in "Candy Land" just south of the climb Big League Chew at 2:00pm on Saturday (11/26). Crown looked to be around 2" to 1' and 90' wide. The slide ran maybe 100'. No skiers were caught. It was triggered as the first skier traversed out onto the intended ski line from the trees which they skinned up. The fracture extended from the tips of the first skiers skis and ran across the slope and underneath a small cliff band. The group skied out on a slightly lower angle slope adjacent to the slide. My group watched from below an adjacent ski run approximately 300 yards away as the slide happened. We had dug a pit on a similar aspect in the area approximately 30 minutes before the slide and found 85cm of snow with a weak layer at 42-45cm which failed CTs but we couldn't get propagation. (CT22, ECTN21). It looked like this was probably the layer that failed in this slide.

Region
Northern Gallatin
Location (from list)
Hyalite - main fork

Wind-loading on Mt Blackmore

Date
Activity
Skiing

Toured up to the NE shoulder on Mt. Blackmore yesterday. Winds were strong and variable, but mostly gusting from the S-SW. A lot of snow was moving around, skin tracks were filled in very quickly, and you could actively see small cornices starting to build on the lee side of the ridge. 

On the descent, I intentionally triggered a small wind pocket in one of the chutes in the cliffs near the trail at 8700 ft. I included a video. It was D1 and about 5 inches deep at the crown. I think just a good reminder that even in the trees, the tops of those chutes get wind loaded and can definitely slide. 

Region
Northern Gallatin
Location (from list)
Mt Blackmore
Observer Name
Haylee Darby

Skier triggered avalanche NE aspect Bridger.

Bridger Bowl
Bridger Range
Code
HS-ASu-R2-D1.5-I
Elevation
7800
Aspect
NE
Latitude
45.82640
Longitude
-110.92900
Notes

From obs: "Triggered a small(d1r1?) wind slab off the bridger chair in bounds at bridger. Little skiers right of bumble chute on the roll over skiers left of bronco. NE face. Rollover around 35 degrees mellowing throughout the run. The face had tracks from earlier today before i triggered the slide. I was able to self arrest and stop myself before being carried. The crown was around 20-25 ft wide and the slide ran roughly 100ft downhill before stopping. Both myself and my partner skied away unharmed."

Number of slides
1
Number caught
1
Number buried
0
Avalanche Type
Hard 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
Wind-Drifted Snow
Slab Thickness
8.0 inches
Vertical Fall
100ft
Slab Width
25.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Crown of skier triggered slide at Bridger on 11/27: "NE face. Rollover around 35 degrees mellowing throughout the run. The face had tracks from earlier today before i triggered the slide. I was able to self arrest and stop myself before being carried. The crown was around 20-25 ft wide and the slide ran roughly 100ft downhill before stopping. Both myself and my partner skied away unharmed."

Bridger Range, 2022-11-27

Blackmore

Date
Activity
Skiing
Snowboarding

Took a lap on the skiers left side of the east face of Blackmore. Didn't see any wind slabs or signs of instability. Wind wasn't really ripping too much. Went along the east ridge a bit and dropped some cornices on an east facing slope that drains to Blackmore Cr. Nothing ripped out besides new snow (about 5" of unconsildated dry pow). The snow on that slope didn't appear to be wind affected either. We did observe weak sugary snow at the ground below the denser snow at the bottom of the pack on high N to E facing slopes.

Region
Northern Gallatin
Location (from list)
Hyalite - main fork