Low-level winds rushing over the Cape Verde Islands off the coast of northwestern Africa created cloud vortex streets, as seen in this true-color Terra MODIS image from January 5, 2005. The vortex streets tend to create patterns of swirls and curves in a roughly symmetrical pattern, though as can be seen here, the lower vortex street is much more disorganized - to the point that the typical features are almost unrecognizeable. Cloud vortices are also known as von Karman vortices.
More information about the Cape Verde islands is available Encyclopedia.com.
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