Lionhead Range

East facing slope.

Date
Activity
Snowmobiling
Region
Lionhead Range
Location (from list)
Watkins Creek
Observer Name
Z. Moser

Avalanche behind lionhead

Date
Activity
Snowmobiling

I was cutting down a hill and this slide broke loose around 20 feet away, no one was hurt I’ll attach screenshots of where we were on maps and a picture of the minor slide. 

Region
Lionhead Range
Location (from list)
LIONHEAD AREA
Observer Name
Jake Anderson

Widespread cracks and collapse in Lionhead

LIONHEAD AREA
Lionhead Range
Code
Elevation
8000
Aspect
E
Latitude
44.68630
Longitude
-111.37500
Notes

From email 1/13: "We observed widespread shooting cracks on all ridges and all NE facing slopes. Cracks would propagate up to 200’ in front. Heavily wind effected sastrugi conditions."

Number of slides
0
Number caught
0
Number buried
0
Problem Type
Persistent Weak Layer
Snow Observation Source
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Red Flag
Advisory Year

Black Bear Canyon Avalanche, W Yellowstone

Other place
Out of Advisory Area
Code
SS-AM-R2-D1.5-O
Aspect
NE
Latitude
45.65530
Longitude
-110.55800
Notes

Riders in Black Bear Cayon saw a small avalanche on a wind loaded slope that recently happened, either on 01/14 or the day before on 01/13. 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Snowmobile
R size
2
D size
1.5
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
12.0 inches
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Widespread shooting cracks in Lionhead

Date
Activity
Skiing

We observed widespread shooting cracks on all ridges and all NE facing slopes. Cracks would propagate up to 200’ in front. Heavily wind effected sastrugi conditions.

Region
Lionhead Range
Location (from list)
LIONHEAD AREA
Observer Name
Oskar Robinson

Remotely Triggered Avalanche in Lionhead

Lionhead Ridge
Lionhead Range
Code
SS-ASr-R3-D2-O
Elevation
8600
Aspect
NE
Latitude
44.71450
Longitude
-111.31800
Notes

While approaching Lionhead Ridge skiers intentionally triggered an avalanche on the steep E, NE facing terrain below the ridge. This likely happened on a buried layer of surface hoar. Lower down widespread cracking was observed that extended well in font of the skiers and on a less steep slope cracking in all directions 50' wide. Along the ridgetop cracking continued and sections of cornice fell and avalanched below. 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Skier
Trigger Modifier
r-A remote avalanche released by the indicated trigger
R size
3
D size
2
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
18.0 inches
Vertical Fall
100ft
Slab Width
1000.00ft
Weak Layer Grain type
Surface Hoar
Weak Layer Hardness
F
Slab Layer Grain Type
Precipitation Particles
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year