This is a photo of mammatus clouds, taken in Weld County, Colorado.
Click on image for full size
Photo courtesy of Gregory Thompson

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Clouds

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Cloud Formation Due to Surface Heating

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Mammatus

Mammatus clouds are pouches of clouds that hang underneath the base of a cloud. They are usually seen with cumulonimbus clouds that produce very strong storms.

Mammatus clouds are sometimes described as looking like a field of tennis balls or melons, or like female human breasts. In fact, the name "mammatus" comes from the Latin word mamma, or breast, because of this.

Last modified November 30, 2007 by Becca Hatheway.

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