"Dangerous Florence", as the official update calls it, is highly likely to bring with it life-threatening storm surges and catastrophic flash flooding, and damaging hurricane-force winds across vast stretches of SC and North Carolina.
"Further strengthening is anticipated and Florence is expected to be an extremely unsafe major hurricane through Thursday", the NHC said in a statement. "Now's the time to prepare".
Florence could hit the Carolinas harder than any hurricane since Hazel packed 130 miles per hour (209 kph) winds in 1954. It was moving west at 13 miles per hour, according to the National Hurricane Center. At that point the storm was centred about 1,170 miles (1,880 km) east-southeast of Cape Fear, North Carolina, the NHC said.
Hurricane Florence is likely to strengthen to a Category 5 storm as it approaches the U.S. where 1.7 million people have been warned to get out of the way.
If the storm stalls, some areas could see feet of rain, especially if downpours focus over the higher terrain in western North Carolina and southwestern and central Virginia Authorities said such volume could cause flash floods, mudslides, and other unsafe conditions.
McMaster said folks should prepare for a lot of flooding in the Pee Dee area.
Gov. Henry McMaster has issued an evacuation order for SC as the area prepares for Hurricane Florence's possible landfall. "People are doing a pretty good job now".
Additionally, one TX-TF1 member is deployed as a Logistics Section Chief for the FEMA US&R Incident Support Team, which has mobilized for Hurricane Olivia, which is set to make landfall in Hawaii on Wednesday morning. The president has spoken to the governors of both Carolinas and Virginia, the White House said Monday.
"It's not just the coast", Graham said. "Any amounts of money, whatever it takes, we're going to do it".
Not only has the storm exploded in intensity, but its zone of hurricane-force winds approximately doubled in size Monday. It will possibly weaken somewhat as it nears land - but that will hardly change the flooding threat.
Florence, packing winds of 140 miles per hour (220 kph), was expected to grow even stronger before making landfall on Thursday, mostly likely in southeastern North Carolina near the SC border, the National Hurricane Center in Miami said.
Even before it officially arrives, Florence will push tall waves far ahead of it.
At this height of the Atlantic hurricane season, Florence was being trailed on east-to-west paths by two other hurricanes, Helene and Isaac. He expects the storm's effect here to be similar to a thunderstorm.
"Hosting a major college football game is a massive undertaking that on a good day involves fans and thousands of state, local and campus personnel, including public safety officials, traveling from all over the area", UNC athletic director Bubba Cunningham said in a statement.
On Tuesday afternoon, data from an Air Force Reserve hurricane hunter aircraft showed that Florence's sustained winds had picked up in speed again, hovering close to 140 miles per hour. "If the storm turns north toward D.C., more airlines will be impacted".
In this September 12, 2018 photo provided by NASA, Hurricane Florence churns over the Atlantic Ocean heading for the US east coast as seen from the International Space Station. Some of these reactors - including Duke Energy's Brunswick and Harris nuclear plants in North Carolina and Dominion Energy's Surry plant in Virginia - may be directly in the hurricane's path, Reuters reported.
On its current track Florence is expected to slam the Carolinas and Virginia the hardest, and all three states have issued emergency declarations to speed preparations.
■ "Life-threatening freshwater flooding from a prolonged and exceptionally heavy rainfall event" from the coast to interior sections.
Still closer to Africa than North America, Hurricane Helene is predicted to head northeast in the Atlantic, then veer toward Europe, the center said.
The ACC also announced that Wake Forest's game against BC in Winston-Salem will now start at 5:30 p.m.to get done earlier with Florence's expected arrival.
"That's good news and bad news", he said. The Center projects wind speed will continue to increase, potentially elevating Florence to a Category 5. Well-built homes can lose walls and roofs.
However, since the Fukushima disaster in 2011, US power plants have installed more safety equipment, such as waterproofing, portable pumps and generators, Duke Energy spokeswoman Mary Kathryn Green told Reuters. Electricity and power can go out for days. "Most of the area will be uninhabitable for weeks or months".
Wherever Florence hits, it will nearly certainly disrupt flights - not only at airports along the coast but also inland after the storm moves ashore.
Andrew was the last Category 5 hurricane to hit the US, said Jeff Masters, co-founder of Weather Underground in Ann Arbor, Michigan. At that level, it would still cause "devastating damage", according to the Saffir-Simpson scale.
A warm ocean is the fuel that powers hurricanes, and Florence will be moving over waters where temperatures are peaking near 30C, hurricane specialist Eric Blake wrote.