Cumulus castellanus (from Latin ''

castellanus A castellanus (or castellatus) (from latin ''castellanus'', castle) is a cloud that displays at least in its upper part cumuliform protuberances having the shape of turrets that give a battlement, crenellated aspect. Some of these turrets are hig ...

'', castle) is an unofficial name of a species of

cumulus cloud Cumulus clouds are clouds which have flat bases and are often described as "puffy", "cotton-like" or "fluffy" in appearance. Their name derives from the Latin ''cumulo-'', meaning ''heap'' or ''pile''. Cumulus clouds are low-level clouds, gener ...

that is distinctive because it displays multiple towers arising from its top, indicating significant vertical air movement. It is a misnomer for cumulus congestus and correspondingly can be an indicator of forthcoming showers and thunderstorms. The

World Meteorological Organization The World Meteorological Organization (WMO) is a specialized agency of the United Nations responsible for promoting international cooperation on atmospheric science, climatology, hydrology and geophysics. The WMO originated from the Internati ...

and the

American Meteorological Society The American Meteorological Society (AMS) is the premier scientific and professional organization in the United States promoting and disseminating information about the Atmospheric sciences, atmospheric, Oceanography, oceanic, and Hydrology, hydr ...

do not recognize cumulus castellanus as a distinct species, but instead classify all towering cumulus clouds as

Cumulus congestus Cumulus congestus clouds, also known as towering cumulus, are a form of cumulus that can be based in the low or middle height ranges. They achieve considerable vertical development in areas of deep, moist convection. They are an intermediate stage ...

.''International Cloud Atlas''

References

Cumulus {{Cloud-stub