Description & Characteristics. Popularly known in the weather community as mammatus clouds, the ‘mamma’ cloud feature can be found amongst six cloud types: cirrus, cirrocumulus, altocumulus, altostratus, cumulonimbus, and stratocumulus. Translated from latin, meaning breast, the six types of mamma clouds are respectively abbreviated as ‘Ci mam’, ‘Cc mam’, ‘Ac mam’, ‘As mam’, ‘Cb mam’, and ‘Sc mam’. Mamma cloud formations are condensed pockets of sinking air that look like cow udders lowering from the base of the cloud.

Even though it was once thought that tornadoes formed from them, mammatus clouds aren’t inherently dangerous. They are commonly found in the vicinity of thunderstorms however. Mammatus clouds are formed the same way cumulus clouds are formed, but in reverse. They are formed by sinking cold air that form pouch-like figures as they’re carried into a warmer layer of air, contrary to the puffs of clouds rising through the convection of warm air.

While they aren’t particularly rare, mammatus clouds can be eye-catching and picturesque, especially at sunset. If you’re a cloudspotter looking for mammatus clouds, pay particular attention to the underside of a thunderstorm’s anvil cloud (incus cloud feature) to increase your chances of spotting them.