At approximately 900 hours, almost the entire amount of the Rocky Points area avalanched naturally. This occurred during a period of high PI and wind loading with mostly Light Category winds. The Soft Slab was predominantly 4 finger in hardness. Debris piles from the Main Rocky Points Chute was the deepest at approximately one meter deep. The initial weak layer was one to two inches above the old snow/new snow interface, and then it appeared to step down to the old snow/melt freeze crust. The weak layer was a light density layer in the new snow, directly above the interface. There was some bonding to the old snow, and this appeared to be a result of the warmth in the old snow surface. Interestingly, there were facets on top of the old snow surface on the highest starting zones in the NNE facing Rocky Points Main chutes. These facets were up to 1mm and were showing signs of rounding. Also, the old snow surface crust in this area was 1 to 2 inches deep and there were moderate sized facets below this crust; and this weakness was just one of three layers that were cracking. Widespread cracking and collapsing was occurring on all slopes with angles > 30 degrees. Slopes between 30 and 35 degrees were cracking and not moving. All slopes with angles > 35 degrees were either already cleaned out or cracking, and very sensitive and easy to initiate activity. The cracking layers were 4 to 8 inches down, as well as at the old snow surface. Propagation was pronounced and rapid.
Another avalanche of note was the Wet Slab observed in the lower half of the Main Dog Lake Chute. See photo. This appeared to be human triggered and produced when the snow surface was very wet/damp. The debris pile here was > one meter deep. It appeared that the trigger escaped off the slab to rider's right. This slide was 55 feet wide, 4 to 6 inches deep, and ran only 100 feet to the flats.
Small section of the Rocky Points Slide Area.
Photo illustrating the multiple Soft Slab Layers that were cracking and avalanching.
Human triggered Wet Slab in the lower half of the Dog Lake Chutes.