The National Weather Service has upgraded a tornado that tore through central Oklahoma last week to EF5, the highest rating given to tornadoes.
The weather service in Norman said Wednesday the May 24 tornado that started in Binger and traveled 75 miles to Guthrie had winds in excess of 210 mph in some parts.
Ten people died in the storm, which traveled across four counties.
Meteorologists from the weather service had been investigating the storm and its damage path for the past week, said Rick Smith, warning coordination meteorologist for the weather service in Norman.
It was data from a University of Oklahoma mobile Doppler radar that convinced officials the twister reached an EF5 level.
“The data that they gathered indicates that over an extended period of time — several minutes — there were winds in the tornado that exceeded that 200 mph threshold for an EF5,” Smith said.
He said the data was gathered near what is believed to be the peak of the storm, near Interstate 40 and the exit for Calumet.
Five people were killed in that area because of the twister, Smith said.
No houses were in the immediate vicinity, but other damage led officials to believe the area might be where the twister reached its peak, he said. Several vehicles were tossed hundreds of yards, a fully functional oil rig was blown over and trees were stripped of their bark.
Although the tornado has been rated EF5, Smith said the tornado did not sustain that intensity the whole time.
Two other tornadoes were rated EF4, one was an EF3, another an EF2 and the other an EF1. One twister is unrated.
This is the fifth EF5 tornado in the United States this year. Three EF5 twisters hit the South during an April outbreak and a tornado that devastated Joplin, Mo., also was rated EF5.
Before April, the last time an EF5 tornado occurred in the United States was in 2008 in Parkersburg, Iowa.