Skier triggered avalanche to ground on Knowles Peak

Knowles Peak
Out of Advisory Area

Skier triggered avalanche on Knowles Peak in the Absaroka Range (outside of advisory area). Avalanche was triggered by 3rd skier on 3/20/2020.

From obs: "I need to report a pretty sizable avalanche that my group triggered today in the Absorokas up the East Fork of Mill Creek on a Northwest facing slope. I believe it was approximately a D3 in scale, the crown was 2-4 feet and about 600 ft wide. It ran to the ground in the start zone and carried debris about 2000ft vertical feet. The debris ran 200ft shy of the the East Fork Rd. It was triggered by the third of three skiers. The skier that triggered the slide took a slightly steeper (approx 34 degrees) line than the other two skiers. The crown started at a convexity in a shallower spot in the snow. We skied this slope last weekend and did a stability test and got a low energy ECT 22. We operated under the assumption that despite some new snow loading the snowpack was generally increasing in stability. We did a hasty pit to see how the new snow was bonding to the old snow surface and it appeared to be bonding well. Solar loading was a concern however this aspect seemed cold and there were no signs of rollers. We really thought this was a good to go situation. The third skier who triggered and was caught lost a ski but was able to ski out of the slide. The two skiers below traversed out of the slide path and kept eyes on the caught third skier. Skiers maintained visual contact at all times. We regrouped and amazingly found the lost ski in the debris pile. It was a scary moment to say the least. Thankfully we are all fine."

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