Photos

From an email: "Our group spotted this huge cornice break on sunday 3/12 while skiing lines into Goose Creek. Its somewhat hard to tell, however the size of the cornice is about the size of a 500sq ft house. Aspect is NE, photo taken on top of Goose Creek headwall looking south." Photo: J. Black

A skier had a very scary encounter when they fell into this hole behind a cornice in Hyalite. They were sure they were not on a cornice, but close enough. Stay as far from the leeward edge of ridgelines as possible. It can be difficult to determine where cornices end, and tempting to travel near them where the snow is more supportable. Warm temperatures will cause cornices to fall naturally, be easy to trigger, and open up holes behind them. Photo: E. Farley

This slab broke naturally on a NE aspect at the base of large cliffs, and was observed on Saturday (3/11). Photo: B. Fredlund

This slide was observed on Saturday (3/11) after a week of heavy snowfall and strong wind. NE aspect. Photo: B. Fredlund

Debris and runout of avalanche likely triggered by cornice fall on Fan Mtn. near Big Sky. Observed Saturday (3/11). Photo: E. Green

Avalanche likely triggered by cornice fall on Fan Mtn. near Big Sky. Observed Saturday (3/11). Photo: BSSP

This slide was triggered by a cornice fall prior to Friday (3/10) on NE aspect in Sheep Creek. The crown was up to 6-10 feet deep and the slide ran to the bottom of the drainage. Photo: S. Barrier 

Riders were happy they weren't any closer when this cornice broke far back from the edge. Photo: H. Menssen

After heavy snow and strong winds, natural avalanches occurred in steep wind loaded terrain. These slides occurred on Wolverine mountain north of Cooke City. Photo GNFAC 

Cornices are large along ridgelines throughout the mountains. Strong winds continue to build them, and above freezing spring temperatures in the future will make them easy to topple. Be extra cautious of slopes below them. Keep a wide distance from the leeward edge of ridgelines. Photo: GNFAC

A snowbiker got too close to edge of the ridge on Lionhead and broke a cornice which triggered an avalanche about 100 feet wide. His sled fell with the cornice but the rider was able to jump to safety. This is the second cornice triggered avalanche that caught riders this week. Photo: GNFAC

From an email: "Here is a wind slab that I triggered from where the picture was taken (About 40 ft away on the ridge line). This is the backside of Lick Creek in Hyalite. The slide was about 100ft wide with a crown ranging between 4-12 inches and did not run very far. A snow pit dug nearby showed no signs of instability, we were confident in skiing the non windloaded terrain nearby." Photo: K. Jamieson

We easily triggered this wind slab at Lionhead. There was a lot of cracking on thick, freshly formed wind slabs today. Heads up!  Photo: GNFAC

A ski tourer south of Cooke City noted several small soft slab slab avalanches breaking in new snow – approx. 7” crown(s). None were deep and they all ran for short distances. Photo: J. Logan

A ski tourer south of Cooke City noted several small soft slab slab avalanches breaking in new snow – approx. 7” crown(s). None were deep and they all ran for short distances. Photo: J. Logan

Skier triggered slab on NW aspect, 8400ft in southern Madison Range. From e-mail: "Skier ski cut top of slope with extra caution, second ski cut, the slope peeled out wall to wall and ran the full length of the gully. Crown depth 35-50cms, ran on older sun/wind crust... High consequence terrain."

Skier triggered slab on NW aspect, 8400ft in southern Madison Range. From e-mail: "Skier ski cut top of slope with extra caution, second ski cut, the slope peeled out wall to wall and ran the full length of the gully. Crown depth 35-50cms, ran on older sun/wind crust... High consequence terrain."

A skier outside of Cooke City triggered this soft slab during a ski cut. The slide failed on an E-NE facing slope and broke 12-16" deep on a thin curst beneath the new snow. The slope was not wind loaded. Photo B. Zavora  

New snow and wind produced small natural avalanches in Tepee Basin in the southern Madison Range. This slide occurred on an east facing slope around 10,000 ft. and only involved the new snow. Fortunatley it didn't step down to deeper layers in the pack. Photo GNFAC 

Track and bed surface of skier triggered slide on Saturday in northern Bridgers. Photo: J. Magajna