No deaths were reported, but some residents of a south Oklahoma City trailer park were injured during the storm and treated at local hospitals, said Dee Patty, a police spokeswoman.
The Oklahoman newspaper reported 12 people were hurt in the incident, though there was no word on their specific injuries.
"I think we got lucky," Patty said. "We've seen a lot worse come through these same areas."
Patty also said two people were hurt during a weather-related road accident. The newspaper reported a third was injured when entering a storm shelter and a fourth person was hurt by flying debris and treated at hospital.
Bears briefly escaped from enclosures at an animal park after a tornado struck the city of Tuttle, about 30 miles (48 km) southwest of Oklahoma City, the Grady County Sheriff's Office said. Officials earlier said tigers had escaped, Reuters reported.
A storm system brought severe weather to several Great Plains states, and the National Weather Service issued a tornado watch for an area stretching from central Texas to central Nebraska. There had been about two dozen tornadoes reported in the area.
Earlier in the day, passengers, visitors and employees at the Will Rogers World Airport in Oklahoma City were evacuated to a pedestrian tunnel for about 30 minutes as the storms moved through the area, the airport said. All flights were canceled through the evening.
The tornadoes flipped cars, downed power lines and snapped trees. Several roads were closed because of debris, the Oklahoma Department of Emergency Management said.
The National Weather Service issued a flash flood emergency for downtown Oklahoma City amid storms and heavy rain in the broader area. It said the airport received 6.9 ins (17.5 cm) of rain for the day.
Severe flooding was reported in the downtown Oklahoma City business district and South Oklahoma City, where local media reported a possible drowning victim after a flash flood.
Grady County officials said 10 homes in the nearby town of Amber were damaged along with 25 homes in Bridge Creek. South Oklahoma City reported a hotel along Interstate 35 was among other structures damaged.
The Oklahoma Corporation Commission said more than 10,000 homes and businesses were without power statewide.