Climbers in Hyalite saw an avalanche near Solstice that happened on 01/21. This avalanche is 1' deep at the crown and with 18" of facets snow below. Photo: R. Meshew
Avalanche Details: Avalanche near Solstice, Hyalite
Northern Gallatin, 2024-01-21
23-24
Natural Avalanche Lionhead Ridge
Lionhead Ridge
Lionhead Range
Code
SS-N-R1-D1.5-O
Aspect
E
Latitude
44.71450
Longitude
-111.31800
Notes
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
1
D size
1.5
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
18.0 inches
Attached Videos
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year
Large collapses in the Bridgers
Texas Meadow
Bridger Range
Code
Latitude
45.84060
Longitude
-110.93300
Notes
Skiers north of Bridger Bowl experienced frequent collapsing while walking across flat terrain near Texas Meadows. Many of the collapses were small but others were "large booming collapses"
Number caught
0
Number buried
0
Snow Observation Source
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Red Flag
Advisory Year
Riders on Lionhead Ridge spotted this natural avalanche that occurred on January 21.
Avalanche Details: Natural Avalanche Lionhead Ridge
Lionhead Range, 2024-01-21
Natural Avalanche Ski Hill
Ski Hill
Lionhead Range
Code
SS-N-R2-D2-O
Elevation
7950
Aspect
E
Latitude
44.70160
Longitude
-111.29300
Notes
A natural avalanche broke on January 21 on Brady's Slope on Ski Hill. Walking to look at the avalanche, we triggered a large collapse and shooting cracks. We dug a pit nearby and got very unstable test results (ECTP4) on a layer of 15-20 mm surface hoar buried 18" deep. Avalanche width and vertical fall were estimated based on Google Earth measurements.
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
18.0 inches
Vertical Fall
300ft
Slab Width
200.00ft
Weak Layer Grain type
Surface hoar crystals
Weak Layer grain size
15.00mm
Weak Layer Hardness
F-
Slab Layer Grain Type
Precipitation Particles
Images
Attached Videos
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year
This natural avalanche failed the morning of January 21 on a steep slope at Lionhead. Photo: GNFAC
Avalanche Details: Natural Avalanche Ski Hill
Forecast link: GNFAC Avalanche Forecast for Mon Jan 22, 2024
Lionhead Range, 2024-01-21
Forecast link: GNFAC Avalanche Forecast for Mon Jan 22, 2024
Very poor stability, and avalanches
Date
Activity
Snowmobiling
There was low visibility at Lionhead with a thick fog engulfing the ridge. We rode to Ski Hill and dug a pit on the south end. As we approached our pit site we noticed a recent avalanche on the steep center section of ski hill. It looked natural, possibly rider triggered in the last 24 hours, 14-18" deep, 225' wide, 200' vertical. SS-R2-D2-O.
Our snowpit had a layer of well-preserved 10-20mm surface hoar below 14" of snow (measured 2.45" SWE in 14" slab). Below that was soft facets, another layer of surface hoar, and more soft facets. We got ECTP4, and PST22/100end on the upper layer of surface hoar. The nearby avalanche probably failed on that surface hoar layer.
We went to look a little closer at the avalanche from a low angle (25 degree) slope above. While approaching we had a large collapse and shooting crack.
A group of riders in the parking lot saw a similar depth recent avalanche a little further up the ridge.
The snowpack is very unstable and avalanches large enough to bury or injure a person are likely to be triggered on any steep slope.
It was snowing lightly all day with calm wind and overcast to foggy skies.
Region
Lionhead Range
Location (from list)
Lionhead Ridge
Observer Name
Alex Marienthal
Large collapses in the Bridgers
Date
Activity
Skiing
Toured out the gate of Bridger Bowl north of Texas meadows. Walking up through the flat meadow we got 10 or so small whumphs and 3 large booming collapses. No remote triggers on the steep terrain above were observed. Snowpit from where the large collapses were triggered is attached.
Region
Bridger Range
Location (from list)
Texas Meadow
Observer Name
Charlie Bayles
Snowmobile Triggered Avalanche in Black Canyon
Island Park
Code
SS-AMu-R3-D2-O
Latitude
44.54760
Longitude
-111.23900
Notes
From interaction at the gas station:
“We were riding out from Island Park. We saw dramatic, collapses, and shooting cracks. I side-hilled a small slope and triggered it 1.5 to 2 feet deep. I have never seen such unstable snow.”
The avalanche likely failed on a layer of surface hoar widespread in the Lionhead and Island Park areas. The avalanche buried part of the groomed road that crosses below this slope.
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Snowmobile
Trigger Modifier
u-An unintentional release
R size
3
D size
2
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
18.0 inches
Vertical Fall
50ft
Slab Width
100.00ft
Weak Layer Grain type
Surface Hoar
Images
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year
A rider triggered this avalanche while side-hilling across the bottom of the slope. The rider was able to quickly turn downhill and avoid the slide. No one was caught. Photo: Anonymous
Avalanche Details: Snowmobile Triggered Avalanche in Black Canyon
Island Park, 2024-01-21