Kevin Gould / NOAA
Before it swept through across the country, leaving some still without power, the now infamous derecho was captured in this June 29th image near LaPorte, Indiana. A huge shelf cloud -- a long, flat formation associated with thunderstorms -- can be seen on the derecho's eastern edge. Says NASA's knowledgable Flickr page, "Derechos have occurred before, and were actually given their name in the late nineteenth century."
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