20-21

Natural Avalanche in Argentina Bowl

Argentina Bowl
Bridger Range
Code
HS-N
Elevation
9000
Aspect
E
Latitude
45.78690
Longitude
-110.93500
Notes

Natural avalanche that ran during or prior to storm morning of 1/5/21. An Avalanche Warning was issued that morning.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
Problem Type
Persistent Weak Layer
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Natural avalanches along Lionhead Ridge

Lionhead Ridge
Lionhead Range
Code
SS-N
Elevation
9000
Aspect
E
Latitude
44.71450
Longitude
-111.31800
Notes

A Custer Gallatin NF Snow Ranger saw a crown line under the rock band on Lionhead Ridge.

On Jan 6, GNFAC forecaster's saw debris below the ridgeline in two paths, but didn't have enough visibility to get more info about the slides.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
Problem Type
Persistent Weak Layer
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Avalanches triggered by groomer near Jardine

Jardine
Out of Advisory Area
Code
SS-AKu-R2-D1
Elevation
7200
Latitude
45.05660
Longitude
-110.61800
Notes

"This morning we had volunteers who were grooming the bear creek cross-country ski trails above Jardine NE of Gardiner in the southern Absarokas outside the forecast area. They witnessed a couple of roadcut slopes above the trail that triggered as they passed by or had recently occurred. Slides were roughly 18" deep and occurred at 7,200 feet elevation."

Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Snowcat
Trigger Modifier
u-An unintentional release
R size
2
D size
1
Slab Thickness
18.0 inches
Slab Thickness units
inches
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year

"This morning we had volunteers who were grooming the bear creek cross-country ski trails above Jardine NE of Gardiner in the southern Absarokas outside the forecast area. They witnessed a couple of roadcut slopes above the trail that triggered as they passed by or had recently occurred. Slides were roughly 18" deep and occurred at 7,200 feet elevation."

Out of Advisory Area, 2021-01-05

"This morning we had volunteers who were grooming the bear creek cross-country ski trails above Jardine NE of Gardiner in the southern Absarokas outside the forecast area. They witnessed a couple of roadcut slopes above the trail that triggered as they passed by or had recently occurred. Slides were roughly 18" deep and occurred at 7,200 feet elevation."

Out of Advisory Area, 2021-01-05

Natural avalanche on Saddle Peak

Saddle Peak
Bridger Range
Code
HS-N-R3-D2.5-O
Elevation
9100
Aspect
NE
Latitude
45.79430
Longitude
-110.93600
Notes

The crown line of this natural avalanche was seen near the summit of Saddle Peak. It likely broke in the morning of Jan 5 during the snowstorm that dropped .8" SWE and prompted an Avalanche Warning.

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
36.0 inches
Vertical Fall
1600ft
Slab Width
600.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Natural Avalanches on Fan Mountain

Fan Mountain
Northern Madison
Code
SS-N-R2-D2
Latitude
45.29810
Longitude
-111.52400
Notes

Three natural avalanches seen on Fan Mountain from Big Sky Ski Resort

Number of slides
3
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
Multiple Avalanches
Advisory Year