Description & Characteristics. Cumulus clouds are the clouds that we all drew as kids. They’re cotton ball clouds, popcorn clouds, and the clouds in the opening scene of The Simpsons. Though they come in different shapes and sizes, they’re generally the easiest type of cloud to pick out of the ten different cloud types. When the average person is asked to visualize a cloud, cumulus clouds are generally the first to come to mind.
The different sizes of cumulus clouds are described by their four associated species. If the cumulus cloud you’re looking at is wider than it is tall, then it’s a cumulus humilis. If it’s as wide as it is tall, then it’s a cumulus mediocris. But when a cumulus cloud is taller than it is wide, known as cumulus congestus, things can get… interesting. If cumulus congestus clouds continue their vertical growth, they’re capable of producing rain, and can eventually morph into a cumulonimbus cloud, or thunderstorm.
If its vertical growth is impressive enough, you might find a cap cloud on top of a cumulus cloud, otherwise known as a pileus cloud. While cumulus clouds are known as low level clouds, cumulus congestus clouds with more extensive vertical growth can rise into the middle level.
Finally, if you see a cumulus cloud that’s ragged and broken up, consider it of the species cumulus fractus. You might witness these clouds in the evening as cumulus clouds begin to dissipate, or perhaps on a windy day.