A shop owner boards up his Wrightsville Beach, North Carolina, building.
He added: "The waves and the wind this storm may bring is nothing like you've ever seen".
"It's what you expect if you have a shift toward more intense storms, is that you'll start seeing intensities you haven't seen before", said Gabriel Vecchi, an atmospheric scientist at Princeton who was one of the study's authors.
"Preparations to protect life and property should be rushed to completion", the agency says.
Schools in southeastern North Carolina were closed on Tuesday and will not reopen until Monday.
Forecasters said Florence was expected to blow ashore late Thursday or early Friday, then slow down and unload one to two-and-a-half feet of rain that could cause flooding inland and wreak environmental havoc by washing over industrial waste sites and hog farms.
Perhaps most significantly, the new research finds that rapid intensification appears to be the key mechanism driving stronger storms in a warmer climate. "Normally, a landfalling tropical cyclone just keeps on going inland, gradually dissipating and raining itself out".
He said the federal government is "absolutely, totally prepared" for Florence.
For many people, the challenge could be finding a safe refuge: If Florence slows to a crawl just off the coast, it could bring torrential rains to the Appalachian mountains and as far away as West Virginia, causing flash floods, mudslides and other unsafe conditions.
OH will also feel the effects of Florence. The storm will likely dump between 20 and 30 inches (50 to 76 centimeters) of rain over its track, causing serious flooding.
He has declared states of emergency for North and SC ahead of the storm, which frees up help from federal agencies. "We're just a strip of land - we're a barrier island", she said.
An evacuation order from Virginia Gov. Ralph Northam applies to about 245,000 people, including parts of the Hampton Roads area and Eastern Shore. But getting out of harm's way could prove hard.
"There's no water. There's no juices".
Trojniar said she and her husband were packing up belongings and plan to stack sandbags around their single-floor home in Wilmington's eerily named Landfall neighborhood near the ocean before checking into a hotel to ride out the storm, with plenty of wine.
TODAY show host Al Roker also warned there are "worries" about a European model for the path of Florence. This could worsen if, as some meteorologists predict, Florence stalls after it makes landfall.
It was located 575 miles (925 kms) east-southeast of Cape Fear, North Carolina, and moving at 17 mph (28 kph) in a west-northwest direction. Florence is still a Category 4 hurricane with winds up to 130 miles per hour.
"Tropical systems don't like to be bothered with wind shear", he said.
"On the forecast track, Isaac's centre is forecast to move across the central Lesser Antilles and into the eastern Caribbean Sea on Thursday".
Hurricane Florence is so wide that a life-threatening storm surge was being pushed 485 kilometres ahead of its "eye", and so full of rain that a swath from SC to OH and Pennsylvania could get deluged.
"This one really scares me", National Hurricane Center Director Ken Graham said.