Skier trigger Deep slab Bear Basin

Bear Basin
Northern Madison
Code
HS-ASu-R3-D2.5-O
Elevation
9600
Aspect
NE
Latitude
45.34360
Longitude
-111.37900
Notes

A four person party triggered this avalanche on Saturday night at around 5:30...One of the members wrote: “It broke on the persistent weak layer underneath a hard windslab directly at my feet, a yard or so from the diagonal rock band near the top of the ridge. The crown was roughly 3 feet at skier’s left and 12 feet at the rock outcrop on skier’s right. The avalanche stepped down to the ground on depth hoar around 250 ft from the crown due to the energy of the first slide. One skier was still on the skin track far below us before the track cut into the fall line. Everybody made it out. I’m sure it was triggered because of the shallower snowpack near the rock band. Snow pits were dug and that persistent layer the original avalanche went on was found but wouldn’t propagate”

From different group on Sunday e-mail: "... we saw  a debris pile that had come down from near the bat ears couloir in bear basin, it looked good size and some dirt and small trees so we decided to get a closer look. It appeared that a group skinned up North fork trail..., bootpacked up bat ears couloir, skied it with no problems, and then decided to  skin up a  real rocky  thinner face  slightly east of the couloir, the skin track appeared to make it to the top of the ridge however there was only 1 downhill ski track and that left from low on the skin track.... N-ne slope guessing 9500-10k ft. Crown was between 1and 10 ft deep, average looked about 2-3 deep, down pretty close to the ground in a lot of  spots.”

From separate e-mail: "D2.5 avalanche on an NE aspect in Bear Basin in the Northern Madisons, 9600ft, there were tracks in the run out (covered by the debris pile)... running on basal facets. Terrain was very rocky, steep, and visibly wind loaded."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Skier
Trigger Modifier
u-An unintentional release
R size
3
D size
2.5
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
36.0 inches
Vertical Fall
700ft
Slab Width
200.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year