In Fayetteville and Wilmington, officials said more evacuations were possible as the Cape Fear River continues to rise above record heights.
Numerous state highways leading out of town were also disappearing under water. Morehead City, North Carolina, had received 23 inches (58 centimeters) of rain by Friday night with more torrents on the way.
Officials said some 1.7 million people in the Carolinas and Virginia were warned to evacuate, but it's unclear how many did.
Two others died in the state from carbon monoxide poisoning caused by a generator inside their home, according to a local coroner.
Bergaw Mayor Pete Cowan warned that the local hospital was not accessible; it had already been evacuated.
"It's the worst feeling in the world to hear people yelling for help, and you can't do anything", she said.
Evacuation orders remain in place for Horry and Georgetown counties along South Carolina's northern coast.
The National Weather Service reported wind gusts of up to 21 miles per hour on September 14 morning in Columbia. These rains are expected to produce "prolonged, significant river flooding".
"This storm is relentless and excruciating", North Carolina Governor Roy Cooper told CNN late last Friday.
The viral video, which has more than 13.6 million views, showed Weather Channel correspondent Mike Seidel in Wilmington, North Carolina, trying to fight the heavy wind as he reported live from the storm on Friday. Areas further inland through southwest Virginia could see as much as 15 inches of rainfall.
A day after blowing ashore with 90 miles per hour (145 kph) winds, Florence practically parked itself over land all day long and poured on the rain.
In New Bern, along the coast, homes were completely surrounded by water, and rescuers used inflatable boats to reach people Saturday.
"And we're not done yet", Graham said, adding that some hard-hit areas could get an additional 15 to 20 inches because the storm was moving so slowly.
"Usually we'd be cleaning roads and done by now", Smith said. "But we're still in the throes of it".
The city of about 29,000, which was founded in the early 1700s, is near the North Carolina coast and is bordered on the east and south, respectively, by two rivers.
"I can not overstate it: Floodwaters are rising, and if you aren't watching for them you are risking your life", Gov. Roy Cooper said. Eventually, a volunteer rescue team from IN arrived with a boat and rescued them.
View of Florence in Wilmington, N.C., on Friday.
"If it goes up to my front step, I have to get out", Quinton Washington said.
Crews from the city and the Federal Emergency Management Agency were working with citizen volunteers to get people to dry ground, Roberts said.
Under a auto port on Route 117 South in Burgaw, Kevin Everett's family cooked pancakes and bacon on a charcoal grill.
In Jacksonville, North Carolina, next to Camp Lejeune, firefighters and police fought wind and rain as they went door-to-door to pull dozens of people out of the Triangle Motor Inn after the structure began to crumble and the roof started to collapse.
Duke spokeswoman Paige Sheehan said about 2,000 cubic yards (1,530 cubic meters) of ash were displaced at the L. V. Sutton Power Station outside Wilmington and that contaminated runoff likely flowed into the plant's cooling pond. "If not we'd be stuck upstairs for the next. how long?" "Don't make yourself someone who needs to be rescued". About 400 people have been rescued.
"Amazing. They did awesome", said Knox, who was stranded with seven others, including a boy who was carried out in a life vest. "I was looking for water moccasins to hit me at any time", he said.
Resident Jay Manning said he and his wife watched with alarm as water filled the street.
He advised never to drive through still or moving water covering roadways - and not to return to hard-hit areas until given an official "all-clear".