The last Category 4 hurricane to plough into North Carolina was Hazel in 1952, a devastating storm that killed 19 people and destroyed some 15,000 homes.
A long stretch of the U.S. Eastern Seaboard remained vulnerable to hurricane and tropical storm conditions, from Georgia north through the Carolinas into Virginia.
Officials in several states have declared states of emergency, including Virginia and Maryland, where coastal areas are still recovering from summer storms. "Disaster is at the doorstep and it's coming in".
The latest forecast indicates that Florence could stall over or close to southeast North Carolina Friday, then could drift west or southwest this weekend.
Subtropical storm Joyce formed in the Atlantic on Wednesday but is not expected to threaten land.
Recruits were set to leave the Marine Corps' largest training installation on the East Coast Tuesday, but those plans changed after South Carolina's governor rescinded an evacuation order as the storm's projected path shifted northward.
Mandatory evacuation orders have been issued in coastal areas of North Carolina, South Carolina, and Virginia, ahead of the arrival of Hurricane Florence this week, but many residents in the area have chose to stay.
While thousands of Marines and their families have already left Camp Lejeune in Jacksonville, North Carolina, there was no mandatory evacuation.
The storm is expected to slow down as it approaches the North Carolina-South Carolina coast, which makes landfall timing less certain, according to the National Weather Service.
Meteorologists at the National Weather Service in Peachtree City concluded early Wednesday that "there is some increased confidence for a wetter and windier period". All seven of North Carolina's ferry routes were shut down. There are concerns that it could knock out power for weeks.
As of midday Wednesday, Florence was hurling 130-mph winds.
While coastal residents frantically boarded up homes and businesses and hit the road, others chose to ride out a storm that is forecast to dump up to three feet (almost a meter) of rain in some areas. "It's going to happen". We're just on a heightened awareness at this point.
"Many of the people here have never seen a storm this strong", he said.
"Our sand dunes are healthy but they're not going to be able to keep back a wall of water like that", he said.