Cap of Cumulonimbus cloud

A scarf appearing above the cumulonimbus cloud is known as Pileus cloud formation. Its a lenticular cloud appearing above the CB cloud. They are formed by strong updraft(small-scale current of rising air) within the cloud at lower altitudes. They are short-lived clouds and indicate a severe weather ahead.

Canon EOS 5D Mark IV and EF 24-105 L lens

Lightroom and Photoshop