What is a derecho?

Published On: Jun 13 2013 10:27:06 AM CDT   Updated On: Jun 30 2013 07:14:45 PM CDT

Duh-what-choo? Find out more about the possible derecho threatening millions of Americans.

Storm ominous over Brooklyn
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Mark Dadswell/Getty Images

The derecho that struck southeastern Kansas, southern Missouri and southwestern Illinois in May 2009 was the first to be classified a "Super Derecho." Thirty-nine tornadoes were reported, along with baseball-sized hail and wind gusts of 106 mph reported in Carbondale, Ill.

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