23-24

Weak layers in Yale Creek

Date
Activity
Snowmobiling

Yale creek opposite side of creek from maintenance shack at 7600 ft with 105 cm on a 27 deg slop 62 deg NE facing.   First column test had an CTE - 1 failing at 75 cm and then CTE-4 failing at 63 cm

ECTN - 5 with no propagation across entire slab   
 

Very deep facets with 4 melt freeze layers with one being 7 cm thick,  surface hose layer very visible and one of the failure layers 

Region
Island Park
Location (from list)
Yale Creek
Observer Name
Brandon Schleicher

Widespread Cracking in Taylor Fork

Taylor Fork
Southern Madison
Code
Elevation
9000
Latitude
45.06070
Longitude
-111.27200
Notes

From Obs: "While riding around we frequently saw large shooting cracks on any slope with a slight wind-load/wind-effect. Near the wilderness boundary we saw these large cracks across the snow surface. In quick hand pits we easily found a weak layer of surface hoar below the recent snow that was 3-4cm long crystals, standing upright!!!"

 

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

Snowmo Remote Triggered Avalanche Taylor Fork

Taylor Fork
Southern Madison
Code
SS-AMr-R4-D1.5-O
Elevation
9300
Aspect
E
Latitude
45.06070
Longitude
-111.27200
Notes

From Obs: "We also saw a small wind-loaded slope that was triggered (remotely) by riders yesterday, and we triggered a similar slope today. These were short slopes, but the slabs broke over 1 foot deep and as wide as the terrain feature, and they were triggered from adjacent flat terrain 10-40 feet away (remotely triggered). "

 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Snowmobile
Trigger Modifier
r-A remote avalanche released by the indicated trigger
R size
4
D size
1.5
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
18.0 inches
Slab Width
20.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Remote Triggered Avalanches, Taylor Fork

Taylor Fork
Southern Madison
Code
SS-AFr-R1-D1.5-O
Elevation
9500
Aspect
E
Latitude
45.06070
Longitude
-111.27200
Notes

From Obs: "At Sunlight Basin, we remotely triggered an avalanche while walking on the flat ridge above a wind-loaded slope. The avalanche broke below a 12" deep slab with 1.5" of snow water equivalent in the slab, and it failed on a layer of large (1-1.5cm) surface hoar."

Number of slides
2
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Foot penetration
Trigger Modifier
r-A remote avalanche released by the indicated trigger
R size
1
D size
1.5
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
12.0 inches
Vertical Fall
150ft
Slab Width
50.00ft
Weak Layer Grain type
Surface Hoar
Weak Layer grain size
15.00mm
Weak Layer Hardness
F+
Slab Layer Grain Type
Wind Broken precipitation particles
Slab Layer Hardness
4F+
Slab Thickness units
inches
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year