Good visibility allowed for absolute certainty no one was below. Standing on old sun crust, I lightly tapped a small 3 ft overhanging cornice. This triggered a wind slab avalanche in what looked like just this afternoons stellars- 10” deep and 20’ wide. A few seconds later the adjacent greyhound bus sized cornice failed spectacularly. There was not much time if any between the cornice and entire slope failure. Looked like 2-6’ deep, 60’ wide running to the flats. Adjacent north slopes were unperturbed yet many massive double overhead monsters loom over the entire ravine. This was an unsupported north facing slope that has repeatedly avalanched this season. Flagstaff was scoured, low density snow had begun to accumulate and wind seemed like it was decreasing. 4pm