This was
your sky.

A Retreating Thunderstorm at Sunset

This retreating cumulonimbus cloud, or thundercloud, exhibits unusual features. It has the bumpy structures of a mammatus cloud on its near end, while simultaneously producing rain on its far end. Photographed in mid-June in southern Alberta, Canada, the cloud moves eastward as the sun sets behind the camera, casting dramatic colors across the sky and highlighting the cloud's unique formations.