Avalanche: Days Fork

Observer Name
Andy Rich
Observation Date
Sunday, December 8, 2013
Avalanche Date
Sunday, December 8, 2013
Region
Salt Lake » Big Cottonwood Canyon » Days Fork
Location Name or Route
Days, Oingo Boingo area
Elevation
10,100'
Aspect
North
Slope Angle
45°
Trigger
Skier
Trigger: additional info
Intentionally Triggered
Avalanche Type
Soft Slab
Avalanche Problem
Wind Drifted Snow
Weak Layer
New Snow/Old Snow Interface
Depth
15"
Width
20'
Vertical
400'
Comments

Traveling from Flagstaff to West Bowl, kicked off 3 avalanches in 3 separate north facing chutes- all very similar. I think it was Jaws, Oingo Boingo, and the thing to the west of Oingo Boingo, but I'm not sure the names exactly- that area anyway. I was stomping on cornices and wind drifts all day and managed to get these three to propagate and run. Starting zones all in the low to mid forties. Two of the paths have consistent angles above 35 degrees and they both ran full track. One of the paths got lower angled just 100' down and the slide stopped there- I'm not sure the angle there but I've seen this path run over that shoulder and to the steeper terrain below before. Seemed like there was a bit of a punch when it was steep- cornices felt brittle and broke easily and quickly- but on lower angle terrain snow was sluggish to move. (I think if it had been warmer today we would likely have had a much more active cycle.) All 3 crowns were 12-16" of fresh wind deposition with the failure at the new snow/old snow interface. Perhaps the most interesting thing was that one of these in particular looked like it wanted to step down to the basal facets- there was cracking and even some movement through the 8" of old snow down to the depth hoar. See photos. Oh, also, one of these I triggered remotely from about 50' away as I approached.

Coordinates