Torrential rain in southeastern Alabama and the Florida Panhandle washed out bridges, sent chest-high water into homes and forced two major military bases to shut down Wednesday. At least one person died, the Florida Highway Patrol said.
"Last night was like a hurricane and tornado all in one," said CNN iReporter Steve Olensky of Perdido Key, Florida, whose 22-foot boat vanished in the storm. "It was blowing and blowing, the rain was coming. It was just incredible. We've been through (hurricanes) Ivan and Katrina, and we've never seen anything like this."
In a neighborhood north of Pensacola, a creek overran its banks, inundating homes and forcing residents to retreat to their attics to await rescue, Escambia County spokesman Bill Pearson told CNN on Wednesday.
Rescuers were reaching the residents on state Fish and Wildlife boats and personal watercraft normally used to patrol the county's beaches, he said. The National Guard was also on the way.
Gov. Rick Scott said crews had completed more than 200 rescues out of 300 requests for help in the state. He declared a state of emergency and warned residents to expect more rain and flooding.
Parts of the region had already received more than a foot of rain over 24 hours, CNN meteorologist Sherri Pugh said.
Naval Air Station Pensacola, Eglin Air Force Base and Hurlburt Field, another Air Force installation, were closed to all but essential personnel, the installations said on their Twitter and Facebook accounts.
The storm swiftly flooded roads and made travel difficult, Pearson said. Reports indicated that three bridges on heavily traveled roads had been destroyed or damaged, he said.
"It was unlike any rainstorm I've experienced," he said.
In nearby Baldwin County, Alabama, the Fish River was reaching historical flooding levels, the county's Emergency Management Agency reported. Many roads in the city of Gulf Shores, Alabama were "totally flooded," the city said on Twitter.
Orange Beach, Alabama, resident Jim Paar said docks that are normally 4 feet above the water outside his condominium are now underwater, and some boats are floating free.
"I've never seen flooding like this, even with a hurricane, you don't see flooding like this," the CNN iReporter said.
Most government offices in the Florida Panhandle were closed Wednesday, as were many schools. Pearson said emergency officials were urging businesses to stay closed as well, and were asking motorists to stay off the roads.
Tides up to 2 feet higher than normal were causing minor coastal flooding and dangerous rip currents, the National Weather Service said.
The rain was the latest work of a slow-moving storm system that has spawned tornadoes and other severe storms since Sunday, claiming at least 36 lives in Oklahoma, Iowa, Arkansas, Mississippi, Alabama, Tennessee and now Florida.
Tens of thousands remained without power in the South, where suspected tornadoes tore through homes and businesses late Monday.
In addition to the Florida flooding death, at least 17 people died because of storms in Mississippi, Alabama and Tennessee on Monday. Those deaths are in addition to 18 others reported from storms Sunday in Arkansas, Oklahoma and Iowa.
Search and rescue efforts were still under way in Louisville, Mississippi, about 90 miles northeast of Jackson, where a tornado flattened a day care center, said Robert Latham of the Mississippi Emergency Management Agency.
Mississippi Gov. Phil Bryant said the twisters inflicted "severe damage" in Louisville. Winston Medical Center, Louisville's major hospital, was also among the buildings hit.
Severe thunderstorms may roar across the southeastern United States again Wednesday, bringing with them a slight risk of hail, damaging winds and tornadoes.
About 37 million people are at risk in places like Jacksonville, Florida; Charlotte, North Carolina; Virginia Beach; Raleigh, North Carolina; and Atlanta, the National Weather Service said.
Heavy rain will be the norm.