While descending the slope I came to a place where the slope rolled over and entered a chute/choke area. I made a right to left slope cut and initiated a propagating crack that immediately ran down the rider's right side of the chute. When I noticed the initial crack I stopped and watched the slide move down the chute into the transition zone. The debris fanned out after leaving the choke and left about 1.5 feet of debris. The slide ran on the old snow/new snow interface from the beginning of all of the storms last week. The snow was cold and dry. There had been brief periods of sunshine, yet with the cold morning temperatures and mostly overcast skies the snow had not become damp. There was no direct sunshine occurring at the time. The aspect was actually SSE. The right flank descended down the chute and at it's apex was at least 15 inches deep. Where the slide broke it was 12 inches deep. There was a solid/marginally slick m/f crust it ran on.