Front Range
AvalancheAnonymous · Dec 29, 2013 · Front Range
Weather
Sunny, blue-bird day. Temps remained in the teens. Light to no wind despite visible transport at times on the higher peaks and ridges. Overnight an additional 3 inches had fallen. Lots of surface hoar formed by 9 am.
Snowpack
Skied on N aspects below treeline and E and W on low angle terrain at and above treeline in really pleasant conditions. Pit dug on E aspect, 31 degrees, 110 cm to ground at 11,250 ft. ECTN. Further prying revealed wind slab layer 25 cm below surface--no real energy or movement with Q2-3 surface on this aspect and pitch but representational of touchy layers seen later in avalanche on steeper north facing slope.
Avalanche
The start zone was due N facing just above tree line at just over 11,000 feet. While traversing on the flat ridge above, a whoomph followed by shooting cracks traveling 20 feet down and across into the loaded wind slab below the convexity. The crown broke about 20 feet wide, 1.5 feet deep, shearing into clean blocks on a Q1 surface. Average slope angle was 38 degrees. The avalanche ran for approximately 300 feet, its greatest width contained to the narrow 30-40 foot terrain feature. Did not step down to ground.