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This photograph of Kelvin-Helmholtz clouds was taken in the foothills of the Rocky Mountains.
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Courtesy of Benjamin Foster/UCAR

Kelvin-Helmholtz

Kelvin-Helmholtz clouds look like breaking waves in the ocean. After wind blows up and over a barrier, like a mountain, the air continues flowing through the atmosphere in a wavelike pattern. Complex evaporation and condensation patterns create the capped tops and cloudless troughs of the waves.

These clouds form when there is a difference in the wind speed or direction between two wind currents in the atmosphere.

Last modified November 30, 2007 by Becca Hatheway.

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