I noticed this Slab release in the distance while going up Mt Superior on June 21. I thought it strange to see a slab avalanche this time of year and thought it worthy of a post. Late this April I was attempting to gain the Pfeifferhorn ridge line on this very aspect (from Maybird), while doing so I noticed a change in density in the snow pack, midway up the slope, stopped and dug a pit. I found 2 layers of graupel about 4-6 inches thick each. The first starting 6in below the surface and the other about 2' below the surface. My partner and I decided the graupel made this slope too sketchy and bailed. I suspect that some rock fall above on the Pfeifferhorn triggered the avalanche shown in the picture and my guess is either the resulting slab avalanche is from the new snow that fell on Sunday June 19th, but I also wonder if it stepped down into this graupel layer that had yet failed to melt and cohere into the snow pack. Either way, pretty impressive to see a slab avalanche occur in the summer time.