Michael Winter, USA TODAY
At least three tornadoes hit Oklahoma City and the metro area Friday night, killing at least five peoples, the Oklahoma medical examiner's office says.
People were trapped in their vehicles as a storm swept down an interstate highway while commuters tried to beat it home.
A mother and a child were killed when their car rolled over, KFOR-TV reported.
About 50 other people were hurt, five critically, the Associated Press reports.
The Oklahoma Highway Patrol said several motorists were injured and others were missing.
One tornado was reported on the ground in Moore, where a mammoth May 20 twister killed 24 people and left the southern Oklahoma City suburb in ruins, KOKH-TV reported.
"Please try to get to a building or safe shelter!" the weather service in Norman tweeted.
Winds were reportedly between 80 and 100 mph. Tornado warnings were posted for several central Oklahoma counties. As the storms raced east, multiple funnel clouds touched down west of Oklahoma City, with TV video capturing one violent tornado on the ground.
Among the injured is a meteorologist from The Weather Channel who is nursing minor injuries after the "tornado hunt" car in which he was riding was thrown some 200 yards by a tornado in Oklahoma, the Associated Press reports.
The SUV that Mike Bettes and two others were riding in was caught up in a storm near El Reno on Friday evening. The Weather Channel said all of the occupants were wearing safety belts and were able to walk away from the banged-up vehicle.
Network spokeswoman Shirley Powell says a Weather Channel team has been in the field for most of May following tornadoes. She says it's the first time one of the network's personalities has been injured while being caught up in violent weather it was covering.
Cars and tractor-trailers flipped on I-40, and motorists were stranded bumper to bumper on I-35 in what the weather service described as "a parking lot."
Emergency officials reported that numerous injuries occurred in the area along I-40, and Randolph said there were toppled and wrecked cars littering the area. Troopers requested a number of ambulances at I-40 near Yukon, west of Oklahoma City.
"We're scrambling around," said Lara O'Leary, a spokeswoman for the local ambulance agency. "There is very low visibility with the heavy rain ... so we're having trouble getting around.
Heavy rain and hail hampered rescue efforts in Oklahoma City. Frequent lightning roiled the skies well after the main threat had moved east. Highways and streets were clogged late into the night as motorists worked their way around flooded portions of the city.
Oklahoma Highway Patrol Trooper Betsy Randolph said troopers found the bodies of a woman and an infant near their vehicle. Randolph said it's not known if the woman was driving into the storm when it hit around 7 p.m. Friday.
Standing water was several feet deep, and in some places it looked more like a hurricane had passed through than a tornado.
In Missouri, the combination of high water and fallen power lines closed dozen of roads, snarling traffic on highways and side streets in the St. Louis area. At the Hollywood Casino in suburban of Maryland Heights, gamblers rushed from the floor as a storm blew out windows and tore off part of the roof.
Rich Gordon, of Jefferson City, said he was on the casino floor when he heard a loud "boom."
"I didn't know if it was lightning or what, but it was loud," Gordon said.
In Oklahoma, storm chasers with cameras in their cars transmitted video showing a number of funnels dropping from the supercell thunderstorm as it passed south of El Reno and into Oklahoma City just south of downtown. Police urged motorists to leave I-40 and seek a safe place.
"I'm in a car running from the tornado," said Amy Sharp, who last week pulled her fourth-grade daughter from the Plaza Towers Elementary School as a storm approached with 210 mph winds. "I'm in Norman and it just hit Yukon where I was staying" since last week's storm.
"I'm with my children who wanted their mother out of that town," Sharp said, her voice quivering with emotion.
At Will Rogers World Airport southwest of Oklahoma City, passengers were directed into underground tunnels and flights were canceled. However, people near the area said they weren't aware of any damage.
Television cameras showed debris falling from the sky west of Oklahoma City and power transformers being knocked out by high winds across a wider area.
As the storm bore down on suburban Oklahoma City, Adrian Lillard, 28, of The Village, went to the basement of her mother's office building with a friend, her nieces, nephews and two dogs.
"My brother's house was in Moore, so it makes you take more immediate action," Lillard said while her young nieces played on a blanket on the floor of the parking garage. "We brought toys and snacks to try our best to keep them comfortable."
Well before Oklahoma's first thunderstorms fired up at late afternoon, the Storm Prediction Center in Norman was already forecasting a violent evening. From the Texas border to near Joplin, Mo., residents were told to keep an eye to the sky and an ear out for sirens.
Friday evening's weather came after flash flooding and tornadoes killed three people in Arkansas late Thursday and early Friday. Three others were missing in floods that followed 6 inches of rain in the rugged Ouachita Mountains near Y City, 125 miles west of Little Rock.
This spring's tornado season got a late start, with unusually cool weather keeping funnel clouds at bay until mid-May. The season usually starts in March and then ramps up for the next couple of months.
Contributing: Associated Press