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Mammatocumulus clouds
Mammatus (also known as mamma or mammatocumulus, meaning "breast-cloud") is a meteorological term applied to a cellular pattern of pouches hanging underneath the base of a cloud, often a cumulus or cumulonimbus. Their color is normally a bluish gray, the same as that of the host cloud, but direct illumination from the setting sun and other clouds may cause a gold or reddish cast. Mammatus can persist anywhere from minutes to hours, diffusing and disappearing over time. Mammatus only occur where cumulonimbus are present; however, they can drift up to 25 miles away from a thunderstorm. The atmosphere must also meet certain conditions, which include a moist and unstable middle to upper atmosphere over a very dry, lower layer of the atmosphere. An updraft then must occur, which shapes the mammatus into the pouch-like shape.
Size: 5100px × 3378px
Location: Bellevue, Nebraska, United States
Photo credit: © Mark Romesser / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: atmosphere, breast-cloud, cellular, clouds, cloudy, cumulonimbus, cumulus, gray, grey, mammatocumulus, mammatus, meteorology, pouches, puffy, sky, storm, thunderstorm, weather