Wind loading and a surprise layer of concern

Lots of "tiger striping" was seen on features exposed to recent winds, although today was fairly calm and we didn't see current wind transport. Settlement cracks around trees grew larger throughout the day. Informal obs like test slopes and mitt pits did not indicate instability, until I looked a little deeper from the surface in a snowmobile trench. I found a thin and subtle rain crust with small facets above and below, and although at 2-3ft deep it was deeper than I'd normally do hand shears on, I tried a few in different locations where I had trenched deep enough, and got clean and planar results. So I went to a north aspect at 8,250ft (pin drop) and got ECTs to propagate just above the rain crust. I think the test slopes we were using were too small and supported by lower angle terrain just below, and were not an effective tool to test this deeper weak layer with strong snow above it. Today was a good reminder not to depend entirely on informal observations, especially when recent weather has been so dynamic.