More rain, flooding in the forecast for US South, Midwest
Flooding (Youtube)

Heavy rain storms will sweep across the U.S. Southern Plains and the Midwest on Saturday and Sunday, potentially causing more flooding that has already forced hundreds to flee their homes and claimed the lives of three people, including a child.

Flood advisories were in effect for parts of eastern Texas northeast through southern Illinois and Indiana and into Pennsylvania as thunderstorms packing heavy rain, large hail and strong winds were in the weekend forecast, the National Weather Service said.

"This will contribute to a significant risk of flash flooding," the service said in a warning. "People in the risk areas should be prepared to encounter flooding."

The service also warned tornadoes could develop throughout the weekend.

Governors and mayors in Illinois, Kentucky and Indiana declared states of emergency for counties along waterways, including the Illinois and Ohio rivers that were expected to rise after reaching near or above their floods stages.

Kentucky Governor Matt Bevin responded to "continued heavy rainfall events which have caused widespread flooding and damage to critical infrastructure across Kentucky" by declaring a statewide state of emergency on Friday.

Hundreds of people in the region were evacuated over the last several days as rising waters reached their homes and nearby roadways, while communities provided sandbags to home and business owners and set up dozens of shelters to house the displaced residents.

"We are 100 percent at the mercy of the water, and we have absolutely no control over what the water does," said Michael Tobin, the emergency management chief in Lansing, Michigan, to the USA Today newspaper.

The flooding claimed at least three lives earlier in the week, including a one-year-old girl who died when she wandered into standing water in a backyard in Central Michigan, according to local media.

A 52-year-old woman was found dead in her car that was submerged in a ditch in Illinois and a 53-year-old man was killed in Oklahoma when his car was swept away by flood waters, local media reported.

(The story was corrected to fix the spelling of tornadoes in paragraph 4)

(Reporting by Brendan O'Brien in Milwaukee; Editing by Mark Potter)