Deyrecho
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Well, a tornado isn't a tornado when it's a deyrecho. That's right, a deyrecho -- a wind storm that can have the severity of a tornado, but it doesn't spin. Mace Bently, a research climatologist at the University of Georgia who wrote about deyrechos in a recent issue of Weatherwise Magazine, tells us about these dangerous wind storms.

"What a deyrecho is, is a very strong, straight line wind event, produced by a complex of thunderstorms, and it's not uncommon to have winds of 80-100 mph with these systems. Not sustained but you can have sustained wind gusts of 50-60 mph over, sometimes, 30 minutes. This would actually occur over an area 250-300 miles in length and up to 100-150 miles wide."

The word deyrecho has not commonly been in use by the public even though it was coined at about the same time the word tornado was, over a hundred years ago.

"It's not real commonly used in the meteorological community either, so its something that, I think with technological advancements now is going to be able to be used in current pretext while a storm is actually occurring. But in the past, without doppler radar or high-resolution satellite imagery, I think it was something that you had to do a post-mortem on the complex of thunderstorms to determine whether or not it was a deyrecho."

The Weather Notebook, which is produced by the Mount Washington Observatory is funded by The National Science Foundation, and underwritten by Subaru -- the beauty of All-Wheel Drive.