By: Meteorologist Courtney Steimann
Updated: Feb 25th 2019

Courtney's Cloud Corner: Mammatus Clouds

Commonly seen after a thunderstorm rolls through, the Mammatus clouds have been known for their pouch-like appearance. As if the cloud has been flipped around and the top of the cloud is now the bottom. A common misconception is that these clouds appear so threatening that they lead to the construction a tornado- which is not true. Usually these are seen after severe weather. These clouds may be associated to cumulonimbus clouds, but more of the anvil part of that cumulonimbus cloud. Anvil clouds are the wispy looking clouds that develop on the upper portion of a cumulonimbus cloud. As discussed in “Courtney’s Cloud Corner: Cumulonimbus Clouds”, when warm moist air rises and cools in an updraft, it forms a cloud. When the updraft loses its momentum, it forms an anvil cloud. Not only can they been seen under anvils but under altocumulus, altostratus, stratocumulus clouds, and much more.


Compared to updrafts assisting in creating clouds, the Mammatus cloud is formed from moist air sinks into dry air. If the higher clouds have such saturated air from the large amount of water droplets and ice crystals, the saturated air will sink. This will cause the Mammatus clouds to appear. If they have larger droplets, it causes it to be harder to evaporate since it takes more energy, which could makes these clouds stick around for a longer amount of time. So more time to amaze at the pleasantry of what Mother Nature has to offer.

Dark color Mammatus cloud.
Mammatus cloud after a Cumulonimbus cloud passed.
Red color on a Mammatus cloud.
The sunset on a Mammatus cloud.