In the tidy world of published cloud atlases, every clump of atmospheric condensation fits perfectly in neat little named bins. But in the real sky, odd formations like this defy easy categorization! A field of altocumulus clouds moved overhead shortly after sunrise, in an environment of very steep lapse rates (a lot of middle level instability!), and fast flow. Short, castellanus-like towers can be seen above a few of the formations in the group, especially at upper middle right. Unlike “pure” altocumulus castellanus, however, these featured wavy, undulating and almost laminar bases most reminiscent of (and likely a skeletal form of) asperatus (a.k.a. asperitas), with some periodicity between cloud clumps like one would expect with undulatus. The entire cloud field raced past in less than 20 minutes. I had never seen anything quite like this before, and may never again!
Norman OK (4 Apr 0) Looking SE
35.2377, -97.4618