Avalanche: Days Headwall

Observer Name
Bart Gillespie
Observation Date
Saturday, November 20, 2010
Avalanche Date
Saturday, November 20, 2010
Region
Salt Lake » Big Cottonwood Canyon » Days Fork » Days Headwall
Location Name or Route
Days-Flagstaff ridgeline
Elevation
10,500'
Aspect
North
Trigger
Skier
Avalanche Type
Cornice Fall
Weak Layer
Facets
Depth
18"
Width
100'
Vertical
700'
Comments

Walking East on Days-Flagstaff ridge we had multiple sensitive cornices that would crack and propagate sympathetically from the weight of walking the ridge. The smaller ones ran on what seemed like a weak layer under the windblown but the largest ran at or very near the ground which was rocky. Most left12-24" crowns with the largest well over 6' and went wall to wall in a chute, over some cliffs, leaving a substantial debris pile in the flats of Days fork. Of note the same ridge line a little further East above Silver Fork about 3-4 hrs earlier was not sensitive at all with large cornice drops producing nothing but a little sluff. The strong Southerly winds on the ridge demonstrated snow transport without substantial snowfall. Winds this strong were visibly moving snow quickly and the conditions were changing hour by hour.

Coordinates