What is the main characteristic of Cumulus (CU) clouds?

The main characteristic of Cumulus clouds is indeed that they develop in a vertical manner. Cumulus clouds are typically fluffy, white clouds with a recognizable shape that resembles cotton balls. They form when warm, moist air rises and cools, resulting in condensation. This vertical development is a result of convection, where heated air rises, leading to the growth of the cloud in the upward direction.

Cumulus clouds can indicate fair weather, but they can also grow into larger storm clouds under certain atmospheric conditions. Their distinctive fluffy tops (which often appear like domes) and flat bases are a hallmark of their vertical development. This characteristic differentiates them from other types of clouds, such as stratus clouds, which are layered and cover the sky more uniformly.