At least 23 people have died after floods swamped parts of West Virginia.
About 9in of rain damaged or destroyed more than 100 homes and knocked out power to tens of thousands of others in the south east of the US state.
About 500 people were stranded overnight in a shopping centre when a bridge was washed away, while dozens of other people had to be plucked from rooftops or rescued from their cars.
State governor Earl Ray Tomblin has declared a state of emergency in 44 out of 54 counties and authorised up to 500 soldiers to assist.
He said: "Our focus remains on search and rescue.
"It's been a long 24 hours, and the next 24 hours may not be much easier."
Greenbrier County Sheriff Jan Cahill described "complete chaos" in his county, one of the hardest hit.
"Roads destroyed, bridges out, homes burned down, washed off foundations," he said.
"Multiple sections of highway just missing. Pavement just peeled off like a banana. I've never seen anything like that."
In the towns of Rainelle and White Sulphur Springs, rescue crews went door to door to check on residents, a painstaking task that could stretch into the weekend.
The state division of Homeland Security reported 15 people killed in Greenbrier County and rescue efforts continue.
An area near the West Virginia-Virginia border received at least 9in of rain while other parts of the state had 3in-5in, National Weather Service hydrologist John Sikora said.
Some of the heaviest rainfall was in Greenbrier County, where The Greenbrier luxury resort and golf course is nestled in the mountains. The course, overrun by floodwaters, is scheduled to host a PGA tour event from July 4.
The Federal Emergency Management Agency said it was sending teams to help with damage assessments.
The governor's office said 14 deaths were confirmed by the state medical examiner. Local officers and rescue workers across the state confirmed the others not yet included in the official tally.
The dead included a four-year-old boy found about a quarter of a mile from where he fell into a creek, which usually runs about ankle deep but rose to about 6ft when Jackson County was pounded with 9in of rain in 16 hours.
Bob Bibbee, with the Ravenswood Fire Department, said the boy was outside with his grandfather, who jumped in after him. Neighbours, alerted by the sound of the family's screams, tried to help save the boy but were also unable to reach him.