Rain had stopped falling across Oklahoma Wednesday and some bloated rivers had crested, but many evacuees were still unable to return to flooded homes in a three-state region and experts warned conditions may yet worsen.

More than two weeks of soaking weather has caused widespread flooding in Texas, Oklahoma and Kansas.

Texas firefighters rescue an unidentified woman and a child after their car became stranded in flood waters under a bridge in Tyler, Texas.
(Jaime R. Carrero/Associated Press)

Flood warnings remained Wednesday for the rain-swollen Neosho River, which forced hundreds of residents to evacuate and blocked key roads in northeast Oklahoma.

The river crested at 8.9 metres at about 1 a.m. Wednesday but wasn't expected to fall below its flood stage of 4.5 metres until Sunday, said Chuck Hodges, a meteorologist with the National Weather Service in Tulsa.

"The upper system that has been almost stationary over Oklahoma and given us all the rain has drifted well south into Texas now," Hodges said. "So for the next several days, there will only be a 20 to 30 per cent chance of rain just about every day."

Tuesday was the 20th straight day that rain had fallen in Oklahoma City.

The Caney River was still rising just north of Tulsa, threatening homes northeast of Collinsville on Wednesday.

At least 1,000 people were out of their homes throughout southeast Kansas, said Sharon Watson, spokeswoman for the Kansas adjutant general.

The evacuees included Frankie Brewer, whose family is waiting for water to recede from their home in Osawatomie, Kan.

"They say, 'God willing and the creek don't rise,' " Brewer said Tuesday. "Well, the creek went right through my trailer."

While the rain had moved out of Oklahoma, rain fell along much of the Texas Gulf Coast during the morning and the weather service said more was likely from South Texas north to the Dallas-Fort Worth area.

"We're going to see one of our heavier rain days of this event," meteorologist Monte Oaks said Wednesday morning in the weather service's Austin-San Antonio office.

On Tuesday, torrential downpours caused more flooding in northern and eastern sections of the state and some people had to be rescued from vehicles. The weather has been blamed for 11 deaths in Texas in the past two weeks and two people are missing.