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This photograph of Kelvin-Helmholtz clouds was taken in the foothills of the Rocky Mountains.
Click on image for full size
Courtesy of Benjamin Foster/UCAR


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 pattern that looks like a wave.

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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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA