Collapsing of a wind slab in Hyalite

"I postholed up to Zach Attack today and dug a pit in the gully a few hundred feet below the route. We found about a meter of snow on the ground, the upper 65 cm being generally unconsolidated (fist-4F hardness) snow largely transported by the wind. Below that was a 5-10 cm MFcr on top of small (1-2 mm) basal facets. Higher up in the gully we found a few isolated winds slabs, and on the way my back down one of my partners felt a wumph as we crossed above a leeward convexity."