Strato Cumulus

Cloud Atlas: Stratocumulus

Stratocumuli are clouds up to 2 kilometres in the air.
They form when a stratus cloud (a thick dense layer of clouds, or overcast) is broken up into smaller 'dots' by an air-stream that turns them over in a circular motion.
Which combined with a near sunset gives you a nice orange pattern.

Taxonomy courtesy of Professor Houze's Cloud Atlas.