Cumulonimbus calvus

Taken during mid October and includes a skyline in London with the magnificent St Paul's Cathedral on the left.  Although it looked as if a shower may have been threatened, London stayed dry that day.

Cumulonimbus capillatus

A dark brooding example somewhat exaggerated in monochrome which I occasionally use to photograph clouds.  It's almost like a piece of Mahler's 5th symphony.

Although this is just a section, these can be huge structures towering vast heights into the sky.  These often occur in the summer during hot stormy weather and often heavy rain storms will follow, possibly with hail or thunder.  I love these!

These are energetic clouds arising from cumulus congests through powerful upward drafts which can develop into Cumulonimbus capillatus shown here.

Cumlulonimbus calvus

A section of a cloud carrying plenty of moisture which can grow to a considerable height, representing the next stage of the sizeable cumulus congestus clouds.