Holepunch cloud over Aurora IL. Picture is a bit crap but whaddyagonnado. These form when a disturbance causes a portion of the cloud to precipitate, and this spreads out in a chain reaction causing a widening hole. You can see the material falling out of the center of the circle.
There ended up being a succession of holepunches but this is the only one I captured. You can see the second hole forming in the distance.
