Skied the skiers left side of South Monitor first it was non wind affected but it was on the verge of going off with the intense sun, decided to try the more N facing right side of the bowl on the second lap. The wind was blowing all day and cross loading the right side corner pocket, once we got to where we were going to ski the slope looked wind loaded and slabbed up, decided to drop a cornice, with no one in the area of course. The decent size cornice dropped and triggered a fairly large hard slab avalanche which propagated to about 150ft wide and left a crown that was 3ft at the deepest and averaged around 20 inches deep, the slide spread out a bit and ran full track to the flats at the bottom leaving refrigerator sized chunks of hard slab and cornice at the bottom of the path, far from a user friendly slide. The slide steeped down about 40ft down the slope, not quite sure if it went into old snow but it seems highly likely if you look at the photo of where it stepped down. The weak layer was lighter density snow under the hard wind slab, it was hard to tell if it did step into old snow because the wind was filling the bed surface in so fast with newly transported snow. The debris pile at the bottom was easily 10ft deep and would have certainly buried a person caught in it.

Photos: Whole deal , where it stepped down, crown, and flank, debris

[Forecaster Comments] - Mark just seems to have the right touch for finding activity along the PC ridgeline.​