Size 3 DPS, Remote Triggered

Alex Grierson , Thursday 2nd May, 2024 6:45AM

Skied near Pedley Pass yesterday (Wednesday). We were surprised to find 40cm of storm snow at treeline tapering to 20cm at 1700m. This was overlying a ~5cm breakable crust on north aspects. There was also large graupel near the bottom of the storm snow. Moderate NW winds were forming wind slabs near ridgetop. A storm slab was also forming throughout the day in sheltered areas. The storm snow appeared to be bonding poorly to the crust/graupel. While skinning along a ridge at 2350m we remotely triggered a size 3 deep persistent slab from 5m away, on a north aspect (see avalanche tab). We couldn’t see the whole start zone due to poor visibility, but we suspect it propagated the full width of the feature. It was a triggered from a thin spot (~60cm deep). This was a big surprise as we were expecting only surface instabilities and were admittedly in too much of a spring mindset. A good reminder of the unpredictability of the deep persistent slab problem, and that a winter snowpack can still be found at upper elevations on north aspects.