"Get out of its way, don't play games with it, it's a big one, maybe as big as they've seen, and tremendous amounts of water", Trump said in a video posted on Twitter.
"This one really scares me", Graham said.
"A storm with the track of Florence is unprecedented".
Tropical storm winds are between 39 and 73 miles per hour, while hurricanes are 74 miles per hour or higher.
More than 1.5 million people have been ordered to evacuate along 300 miles of coastline.
"In light of the storm's forecasted southward track after making landfall, I encourage Georgians to be prepared for the inland effects of the storm as well as the ensuing storm surge in coastal areas".
Speaking about the Wilmington area and its surrounding beaches in North Carolina, a Federal Emergency Management Agency (FEMA) official said the inland flooding threat was "extreme".More news: Hurricane Florence Approach Swamps North And South Carolina
"This is not going to be a glancing blow", Byard said at a press conference in Washington, warning of power outages, road closures, damage to infrastructure and potential loss of life.
Its trajectory showed its center most likely to strike the southern coast of North Carolina by late Thursday or early Friday, the National Hurricane Center said.
However, her agency was prepared to assist neighboring SC and North Carolina, which are in the landfall bullseye for Category 4 Hurricane Florence, according to some computer models.
The latest prediction shows Florence traveling north along the Virginia coast, and then tacking south back through North Carolina, bringing additional rain to the coast, before heading west to Northwest Georgia.
Florence was about 550 miles off shore Wednesday morning and is expected to bring rain, wind and a massive storm surge to the Carolinas by Thursday.
Despite all that, 65-year-old Liz Browning Fox plans to ride the storm out in the Outer Banks village of Buxton, North Carolina, despite a mandatory evacuation order.
Another FEMA spokesman said: "I need to re-emphasise this is a unsafe storm".
As of Tuesday, more than 1.7 million people in the Carolinas and Virginia were warned to clear out.More news: Millions prepare for potentially catastrophic Hurricane Florence
"Not much has changed since this morning", meteorologist Chris Fisher from the National Weather Service said.
Hurricanes Katrina and Harvey, which decimated parts of the Gulf states and Texas in 2005 and 2017 respectively, cost more than $125 billion.
On Wednesday, we got an inside look at the planes at Lakeland Linder Airport.
"You'd have to expect, just based on the forecast, that it's going to be a significant impact to businesses", including prolonged disruptions, said Rick Miller, head of the USA property practice at Aon Plc. "I was in the same house and it stood fine".
The footage was captured on Monday, September 10, as the storm bears down on mainland USA, first heading towards North Carolina but now possibly veering slightly more towards SC.
"Disaster is at the doorstep and is coming in". The only exception was Edisto Beach - that and other areas to the north remain under evacuation orders.
"The risk is probably not that rain is going to fall into the pits", Holleman said "The risk is that land and water will compromise the dams".More news: WNBA Finals: Storm sweep Mystics to win third title