What is a derecho?

Published On: Jun 13 2013 10:27:06 AM CDT

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

Storm chasers, lightning
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REUTERS/Gene Blevins

That's what happened last year, when  a powerful storm system blasted from Indiana to Maryland. Considered the largest of its kind, it killed more than a dozen people, leaving millions in the dark and shutting down Netflix as well as other online services that relied on Amazon's Cloud servers.

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