altocumulus

Altocumulus clouds develop from 2400 to 6000 m or more because of convection. They are round masses or rolls but are smaller than stratocumulus and bigger than cirrocumulus. The colour is white or light grey. They usually don't bring rain but sometimes they announce a drops. Some pictures are taken from the airplane and during the sunset so the sky colour turns from blue to yellow to pink.

photo -> nature -> clouds -> medium level clouds -> altocumulus