The deadly tornado that ripped through Joplin, Mo., Sunday evening, killing at least 89 people, intensified with unprecedented speed, according to storm trackers.
The supercell thunderstorm that produced the devastating twister formed over Kansas. The National Weather Service received its first report of the tornado at 5:34 p.m. local time, from west of the Missouri-Kansas border.
Seven minutes later, there were reports of a tornado within Joplin's city limits, about 7 miles (11 kilometers) east of the first sighting.
"Every storm is a little different, but this storm went from what was just a funnel cloud to a very strong, very large and very wide and obviously very damaging tornado in a very short time," in under 10 minutes, said Andy Boxell, a meteorologist with the National Weather Service in Springfield, Mo.
"It's something that I've not seen personally, and certainly it's a rare thing to see," Boxell told OurAmazingPlanet.
Comment: Enhanced Fujita Scale: EF1 is an indicator on a scale of EF0-EF5. An EF1 scale Storm has sustained winds of 86 - 110MPH or 138 - 178km/h.
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