No deaths were reported from the tornado that struck shortly after 1 a.m. in the midtown area of Tulsa, according to city of Tulsa spokeswoman Kim Meloy.
National Weather Service meteorologist Mike Teague said the tornado was rated an EF2, with wind speeds of 111-135 mph and that two smaller, "probably" EF0 tornadoes with winds of 65-85 mph were seen shortly afterward on radar near Inola and Claremore, about 25 miles (40 kilometers) east and northeast of Tulsa.
Emergency Medical Services Authority spokeswoman Kelli Bruer said the ambulance company transported a total of 13 people to area hospitals, eight from a TGI Fridays restaurant, which lists its closing time as 1 a.m., four from a 24-hour Whataburger restaurant, and one person who was in the area.
St. Francis Hospital spokeswoman Lauren Landwerlin said about 30 people were treated at the hospital. Meloy said many people were taken to hospitals by private vehicles.
One of the most severely injured was in TGI Fridays and the other was inside the Whataburger, Bruer said.
The timing of the storm was fortunate, according to Meloy, because hundreds, if not thousands of people were in the area only hours earlier.
"It's a highly commercial area with a lot of people normally in there. There's a mall, there's a movie theater," in addition to the restaurants, Meloy said. The area also includes some industrial sites.
The mall had closed at 9 p.m. Saturday, according to its website. A phone call to the mall was not answered Sunday.
The estimated one-square-mile area remained blocked off Sunday while crews worked to remove the debris, Meloy said.
Resident Rayvonne Marcheselli told The Associated Press she received a tornado warning on her cellphone about five minutes before the storm hit and was able to get her 16, 17, and 18-year-old sons downstairs in their two-story home.
"They pounced on the couch and then the 'boom' hit, and I was like 'what was that?'" Marcheselli said.
Later Sunday morning, she saw the damage.
"Like a ... razor, it just took out a path of trees through here," Marcheselli said.
Some of the damaged power poles leaned precariously over roadways, with power lines dangling to the ground, and forced the closing of Interstate 244 for about two hours immediately after the storm. The wind ripped a "Pet Smart" sign down and it ended up dangling from power lines. The TGI Fridays restaurant was extensively damanged.
More than 17,000 customers were without power at one point and about 4,200 remained without electricity Sunday afternoon, according to Public Service Company of Oklahoma.
Tornadoes are generally associated with spring months, but weather service meteorologist Amy Jankowski said they can occur any time.
"I wouldn't say outrageously rare, but it is uncommon," to see an August tornado, Jankowski said.
The weather service said thunderstorms with dangerous lightning the most likely threat were expected to continue through Monday.
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