“Throughout the world, one of the most favored clouds among skywatchers is the cumulus cloud. The puffy, fluffy, whimsical clouds add character to beautiful sunny days, yet they become quite dramatic when they grow into huge, stormy thunderheads.
The word ‘cumulus’ is Latin for the word ‘heap’. When warm, moist air rises, water vapor eventually cools and condenses on particles (called condensation nuclei) into tiny water droplets. As the process continues, water droplets continue to accumulate upwards, creating heaps visible in the sky as white, fluffy clouds. Essentially, a cumulus-type cloud is a cloud that develops in a vertical direction from the bottom up.”