Touchy conditions in the Cypress backcountry

Laura Barreca

Snow conditions were: Heavy, Powder, Wind affected. Weather conditions were: Foggy, Stormy, Windy. We rode: Mellow slopes, Open trees. We avoided: Steep slopes. Riding quality was good.

Avalache Conditions: Slab avalanches today or yesterday. Whumpfing or drum-like sounds or shooting cracks.

Avalanche

Storm snow rapidly piled up as we skied a few laps this morning, quickly covering our tracks. We noticed shooting cracks with almost every step, with cracks growing bigger as the day went on. We triggered two small (.5) slides on convex rolls, with the new storm snow sliding not on the buried crust, but on a shallower layer of storm snow. The crowns were 10-15cm high, and the run length was around 10m. The buried crust layer (which was not exposed in these slides) was another ~15cm deeper. We also observed 3-4 natural size 1s in the same area, on steeper slopes. Viewing from a distance, it looked like the crown of the biggest one was around 20cm thick, 25m wide, with a run length of about 40m. These naturals occurred while we were skiing (likely at around 12:30 - 1pm), as we saw no evidence of them on our first run, but noticed them later in the day. Based on our hand shear, it looked like there was a 20-25cm layer of storm snow sitting on top of a 5cm layer of packed wet snow, which in turn sat directly on top of the buried crust. Hand shears yielded easy planar results about 15cm down (the layer on which we observed the slides going). Occasionally, our hand shears showed resistant results on the interface between the wet and dry (fresh) snow. We did not witness any avalanches occurring directly on the crust, nor did we get any hand-shear results on the crust. By the time we were leaving (around 1:30pm), we noticed significant warming, with the snow becoming heavy and grabby.