At sunset and after some heavy downpours of rain I noticed these huge towering cloud formations roaming the skies as they moved off. I believe this type of cloud is called Cumulus Congestus, as well as Towering Cumulus. They have considerable vertical development and are usually taller than wider, and can look like giant monster cauliflowers roaming the skies.
Rear garden, Staffordshire, England. May 2017.