The potential for Wind Slab avalanches will relate directly to how much new snow we receive overnight and throughout the day on Sunday. If we only get an inch or two of new snow, the danger will be pretty minimal. If it starts to pile up more than that we could see significant wind slabs building on lee terrain (primarily North in this case).
Much of the southern and western part of our region was blanketed with a thin melt-freeze crust today which minimized wind slab development. With new snow in the forecast, we will see fresh wind slabs build tomorrow. The size of these will depend on just how much snow we get. Wind deposited snow (and thus wind slab avalanches) can be 3-5 times as deep as the new snowfall in sheltered areas.
Much of the region around Bachelor had a thin melt freeze crust on the surface today (see Phil's observation or my profile). Unfortunately this was covering up all of our nice soft snow from last week. The rain crust from early January now resides 20-50 cm. below the surface. In some places we've been finding faceted snow grains near this crust, and particularly below it; sometimes we'll get a sudden planar or sudden collapse in a compression test on this layer. Other times it seems totally unreactive, like in my profile below Tumalo bowl today. We haven't seen a single avalanche associated with this layer, and I'm not anticipating we will in the near future. If you are digging, this (along with the soft snow above) is where to target your tests.
