What is a derecho?
A weather system known as a derecho is about to descend on the Midwest and Mid-Atlantic. But what is it?
Thu, Jun 13, 2013 at 02:46 PM
A shelf cloud along the leading edge of a derecho in Minnesota. (Photo: NOAA/Wikimedia Commons)
Last year, a historic derecho ripped across the Mid-Atlantic United States, producing the highest wind gusts ever recorded in the months of June or July; 5 million people lost power and 22 lost their lives.
A derecho? It sounds more like a snack food than a deadly storm.
Pronounced deh-REY-choh, it is a widespread, long-lived windstorm associated with a band or shelf of rapidly moving thunderstorms. The word means "straight" in Spanish; it refers to the long lines of wind damage these dastardly storms leave in their path.
As USA Today explains, to qualify as a derecho, the storm must be at least 240 miles long and have winds of at least 58 miles per hour. That said, classic derechos have winds that top 100 miles per hour, causing extensive damage, power outages and no end of abuse to trees.
Watch the video below to see how they form:
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