The NWS says southern and central portions of North Carolina into far northeast SC are expected to report an additional 10 to 15 inches of rainfall - with storm totals between 30 and 40 inches along the coastal areas south of Cape Hatteras. It's the most powerful storm of 2018 so far. "We got thrown into mailboxes, houses, trees", said Holt, who had stayed at home because of a doctor's appointment that was later canceled.
The rest of SC into western North Carolina and southwest Virginia is expected to report 5 to 10 inches of additional rainfall, with isolated cases of 15 inches.
It diminished from hurricane force as it came ashore, but forecasters said the 350-mile-wide storm's slow progress across North and SC could leave much of the region under water in the coming days.
Florence is 350 miles (560 km) wide and has travelled 4,000 miles across the ocean from west Africa.
At least five people have died in storm conditions in North Carolina, according to authorities. Water rescues were also underway, although it was hard to know how many had occurred.
"Hurricane Florence is powerful, slow and relentless", Cooper said.
"Please be safe and be smart and use your common sense", Cooper added.
Top sustained winds are now about 100 km/h and the storm is moving to the west-southwest at 7 km/h - a track that is expected to continue through early Saturday.
Tropical storm-force winds extend outward up to 175 miles (280 kilometers) from its center.
Flash flood are expected to his the south-east coast as the storm moves across land.
The dead included a mother and baby who were killed when a tree fell on their home in Wilmington, North Carolina.
Police confirmed the fatalities on Twitter, saying the father of the child was being transported to a local medical centre to be treated for his injuries. Another person died from a cardiac arrest when emergency services could not reach her, due to downed trees blocking their path.
"[It's] very eerie, the wind howling, the rain blowing sideways, debris flying", Orsa, who lives nearby and fears splintering trees will pummel her house, told The Associated Press. A 77-year-old man was apparently knocked down by the wind and died after going out to check on his hunting dogs, Lenoir County authorities said.
Morehead City, North Carolina, had received 23 inches of rain by Friday night, and forecasters warned Saturday morning that parts of the Carolinas could get up to 15 inches more. North of the landfall, another 150 people near the town of New Bern required rescue from floods along the Neuse River.
It already had, in Beaufort County and its capital city, Washington, where 300 people were rescued from flooded homes.
Forecasters believe the biggest danger right now is the water, not the wind.
It was expected to begin pushing its way westward across SC later in the day, in a watery siege that could go on all weekend. CORRECTING TYPO IN CITY NAME People are rescued by members of the U.S. Army during the passing of Hurricane Florence in the town of New Bern, North Carolina, U.S. September 14, 2018.
About 20,000 people hunkered down in 157 schools, shelters and a coliseum in Winston-Salem.