Photos

This recent avalanche occurred near Hyalite Peak and appears to be triggered by a goat. It occurred on a ENE aspect.

This avalanche happened while a skier was ascending this slope. It appears to be heavily wind loaded and broke 4 feet down at its deepest. This slide was about 70 feet wide and ran 250 feet downhill relatively slowly and no one was injured.

This slide was spotted on Wednesday (12/11) on a west facing slope above Goose Lake near Cooke City. It was 6 feet at it's deepest. Other slides on other aspects were seen as well. Photo: A. Steckmest

This slide occurred on Hardscrabble Peak in the northern Bridger Range. Skiers were removing climbing skins from their skis at the red "X" when it occurred. They are not sure if they triggered it or not. They also reported very strong winds blowing from the north that were moving lots of snow and loading southerly facing slopes. Photo: A. Blessing

This slide was triggered by a skier only 200 ft below the Bridger Ridge on the west side of the range which is NOT part of the ski area. It was a west facing slope. He found many stiff wind slabs resting on very weak facets, a perfect combination for avalanches. He also experienced lots of collapsing and cracking. Photo: A. Whitmore

This slide was triggered by the Bridger Bowl Ski Patrol. It did not fracture over a wide area, but it broke deep in the snowpack. Last week's -20F weather weakened the snowpack making these slides possible. Photo: P. Clayton

These remotely triggered avalanches had a fracture that occurred across 900 feet in non-wind loaded snow with a very very soft slab. This was very surprising and a warning sign of more avalanches and bigger avalanches when more snow and wind comes. Photo: GNFAC

Six individual avalanches were triggered at the same time on this ESE facing slope in the Third Yellowmule drainage from low angle terrain about 900 ft away. These are called remotely triggered avalanches. While they are small and none would bury you, they are a major warning sign because they show the ability of weak facets near the ground to fracture over long distances. When we get more snow and wind, we will get more avalanches and bigger avalanches. Photo: GNFAC

These two slides were triggered remotely by snowmobilers riding in the trees above the Beaver Creek drainage along Buck Ridge near Big Sky. These slides were similar to ones triggered in 3rd Yellowmule. Photo: GNFAC

A climber triggered this at the top of the ice climb, The Fat One in Hyalite.  Luckily he hooked a tree with his ice tool before it broke.  Wind slab on facets fractured with a light touch.  Wind slabs are not to be trusted. Photo: Montana Alpine Guides

The weak layer was large factes underlying the slab of ice.  It fractured just like a snow avalanche. Very, very unusual.  Photo: GNFAC

Walking back to my pack I triggered this 1 foot thick slab of ice!  The ice formed over a thick layer of facets and fractured just like a snow avalanche.  I have never seen anything like this before.  You could scoop out the facets with your hand. We were on safe terrain, but it could have been ugly if it pushed you off a ledge. As if we don't have enough to worry about snow avalanches, now we have to think about ice slabs?! Photo: D. Chabot

Climbers triggered this pocket of windblown snow yesterday, but as I was cutting out my column for an ECT today, all the remaining hangfire released.  It was a 1 foot thick hard slab of wind blown snow over well developed facets.  I have never seen this avalanche so big.  Instability like this is indicative of bad avalanche danger higher up and on other climbs. Photo: GNFAC

This snowpit was dug on the south side of Carrot Basin.  The layer of most concern is 26cm off the ground: a layer of sugary facets. The snowpit profile is HERE.

This explosive triggered avalanche occurred on the South Face of Lone Mountain in the Otter Slide above Lenin. Most slides breaking deep in the snowpack have occurred on north aspects and this was the first one so far on a south aspect. The ski patrol did not think it could have been triggered by a skier but that's a chance they can't take. Photo: Big Sky Ski Patrol

This small natural avalanche was observed in the northern Gallatin Range near Hyalite Peak. It likely occurred during or immediately after the storm earlier in the week. This slide stayed confined to the storm snow and did not step down to deeper layers. It remains possible for skiers or riders to trigger similar avalanches in steep terrain. Photo GNFAC  

Doug Chabot inspects the crown of the 3-4 foot deep, soft slab avalanche.  It was on a northeast facing slope and fractured on a thin layer of small-grained facets. The slope angle was 35-37 degrees. Photo: B. Fredlund.

The left avalanche was approximately 150 feet wide and ran 320 feet vertical. Photo: B. Fredlund

This small natural avalanche was adjacent to the two bigger slides.  Small avalanches are Mother Nature's red flags that similar slopes are unstable. Photo: B. Fredlund

It appears that the right avalanche was triggered by a snowmobiler on Wednesday, which also released the smaller slide on the left sympathetically. Buried facets 50cm off the ground were the weak layer. Photo: B. Fredlund