Florence is also expected to lose speed and "hover" once it reaches the coast, which will intensify the impacts of its heavy rainfall and storm surges, Ken Graham, director of the National Hurricane Center (NHC), said in a Facebook Live update earlier today.
As of 11 a.m., the Category 4 storm was centred 485 miles (785 kilometres) southeast of Wilmington, moving at 15 mph (24 kph) with the potential for 1 to 3 feet of rain in places - enough to touch off catastrophic flooding and an environmental disaster, too, if the water inundates the region's many industrial waste sites and hog manure ponds.
"We will experience power outages, we will have infrastructure damaged, there will be homes damaged, and there will be debris on the roads", said Jeff Byard, an official from the Federal Emergency Management Agency.
The NHC stressed, however, that while a slow weakening is expected over the next 24 hours "Florence is still forecast to be an extremely risky major hurricane when it nears the USA coast late Thursday and Friday".
After making landfall this Friday (Sept. 14), the massive storm will now "wobble" southward and then head west, making a "big, grand tour" of the southeastern United States, U.S. Fish and Wildlife Service (FWS) meteorologist Kevin Scasny said in a statement released today (Sept. 12).
"I ask all Georgians to join me in praying for the safety of our people and all those in the path of Hurricane Florence", Deal said. "I encourage Georgians to be prepared for the inland effects of the storm as well as the ensuing storm surge in coastal areas".
Incredible time-lapse footage filmed from a hurricane-hunting plane shows what's it's like to fly through the eye of Florence, the storm that's already forced more than 1 million people to evacuate.
A state of emergency has been declared in D.C. and in states, including Virginia and the Carolina's.
One grocery store in Myrtle Beach, South Carolina, sported a plea for divine intervention - with forecasters warning that the threat of devastation remains high despite the downgrade.
SC authorities have turned four motorways into one-way routes away from the coast to speed the exodus.
This is the third time SC has had to cancel a game due to weather in the last four years.
"Today is the time to get your preparedness actions complete", he said.
Kevin Miller, a 50-year-old electrician, said he planned to ride out the storm at his home near Charleston.
Its governor, Roy Cooper, told residents "the time to prepare was nearly over".
Another joker said: 'Looks like tropical storm Floyd has penetrated Florence, we will be having a baby shower for the little sprinkle that's due in 9 months'.
Florence is being trailed in the Atlantic by two other storms - Hurricane Helene and Tropical Storm Isaac.
"Water, generators, all the people here, we have everything we need", he said.