Jason Thompson of the Big Sky Ski Patrol took this picture of a low angled slope that cracked. The patroller in the pic is standing on the ground since the snow is unsupportable with facets.
08-09
GRAVELLY RANGE AVALANCHE FATALITY
SYNOPSIS:
A group of 14 snowmobilers went into the Black Butte area of the Gravelly Range when one of the riders triggered an avalanche. He was caught and fatally buried. The avalanche released on an east facing, wind-loaded slope. The slope angle was approximately 35-40 degrees with the crown face 1-4 feet deep, averaging 2 feet. The avalanche was estimated to be 200 feet wide and 75 feet vertical. US Classification of the avalanche is HS-AM-D2-R4-O.
GPS Coordinates for the slope is
N 44.54’ 45”
W 111.53’ 59.2”
The X marks the spot where the rider got stuck. The crown is 15 feet at its thickest and tapers to 2 feet thick at its edges. Photo: Tim Peare
Looking down the avalanche path from 2/3 height. It slid on facets on the ground and fractured up to 15 feet deep. Rescuers can be seen on the debris 1,000 feet below.
Rescuers search for the body of a snowmobiler caught in an avalanche on Crown Butte which is adjacent to Daisy Pass near Cooke City.
This slide was triggered by a snowmobiler. The X marks the spot he was buried. The slide was 200' wide x 75 feet vertical, 2' avg crown. It was a hard, wind slab that released on facets near the ground.
This small photo was captured from a video camera immediately before the avalanche was triggered on Crown Butte. This slope was covered with tracks which subsequently got wiped out in the slide.
Lionhead ridge had this avalanche release in the last 36-48 hours. It's a wind-loaded slope above the backcountry trail into the north facing bowls. Photo by Ben Fuglie