22-23

Natural avalanches on NE face of Fan

Date

Saw natural avalanche debris below the cliffs on the NE face of Fan from the resort. Tons of wind loading the last few days. Light wasn't good to get a clear picture. Looked like a few different smaller avalanches but could have gone all at once. 

Region
Northern Madison
Location (from list)
Fan Mountain
Observer Name
Edward North

Skier triggered hard wind slab at Bridger

Bridger Bowl
Bridger Range
Code
HS-ASc-R2-D1.5-I
Elevation
7800
Aspect
NE
Latitude
45.81700
Longitude
-110.92500
Notes

Skier triggered wind slab avalanche around 2pm, along the edge of north Bowl and Bronco near "The John". Crown 6-10" deep and 30 feet wide, hard slab of recent drifted snow. HS-ASc-D1.5. Strong wind blowing steady from the south-southwest and transporting snow, filling in tracks rapidly.

Immediately after this slide, I saw what I assume was skier triggered, slide of similar size a little further down the bowl with crown drifting in. Beacon check of debris produced no signal, barely deep enough to bury someone.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Skier
Trigger Modifier
c-A controlled or intentional release by the indicated trigger
R size
2
D size
1.5
Bed Surface
I - Interface between new and old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
10.0 inches
Vertical Fall
200ft
Slab Width
30.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Skier triggered hard wind slab at Bridger

Date
Activity
Skiing

Skier triggered wind slab avalanche around 2pm, along the edge of north Bowl and Bronco near "The John". Crown 6-10" deep and 30 feet wide, hard slab of recent drifted snow. HS-ASc-D1.5. Strong wind blowing steady from the south-southwest and transporting snow, filling in tracks rapidly.

Immediately after this slide, I saw what I assume was skier triggered, slide of similar size a little further down the bowl with crown drifting in. Beacon check of debris produced no signal, barely deep enough to bury someone.

Region
Bridger Range
Location (from list)
Bridger Bowl

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

View from top 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

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

Pits results in beehive area

Date
Activity
Skiing

On a northeast facing slope at 9,100' near the ridge that divides middle and beehive basins my party dug a pit that was 65 centimeters deep, the extended column test had a score of ECTN 19 at 37cm. The layer at 37cm from ground appeared to be 5cm of sugary fist density snow sandwiched between layers of 4finger density snow.

We observed small shooting cracks up to 6 inches while traveling through freshly wind loaded snow near ridgelines. 

Region
Northern Madison
Location (from list)
Middle Basin
Observer Name
M. Gaffney

Skier triggered avalanche NE aspect Bridger.

Date
Activity
Skiing

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. Tons of people touring up bridger today, many without backpacks/ beacon shovel probe.

Region
Bridger Range
Location (from list)
Bridger Bowl
Observer Name
James Knudtsen