13-14

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

These avalanches released early in the week after the larege snowstorm: north to northeast facing slopes that likely ran on faceted snow 1-2 feet off the ground.  Photo: B Fredlund

Cooke City

This slide was triggered by the Big Sky Ski Patrol on the north side of Lone Mountain (formerly Moonlight Basin). It broke about 3 feet deep on facets near the ground. This slide was triggered with explosives, and it is notable because it occurred on a slope that has no history of producing avalanches. Photo: Big Sky Ski Patrol

This natural avalanche was one of at least 20 observed on Tuesday, Dec 3 near Cooke City following a storm that deposited 3 inches of snow water equivalent which was over 2 feet of heavy snow. Photo: B. Fredlund