Florence - with its 130-mph sustained winds, anticipated 13-foot storm surge and projected 40 inches of rain in some stretches - is slated to sock the Carolinas and Virginia with a "Mike Tyson punch" late Thursday into early Friday, FEMA chief Jeff Byard said Thursday.
Meanwhile, what could be the world's most risky storm at the moment is Super Typhoon Mangkhut, which now has winds of 165 miles per hour (with 200 miles per hour gusts) and is taking aim on the Philippines, according to the Joint Typhoon Warning Center.
Florence is lashing the state with "heavy rainbands with tropical-storm-force winds spreading across the Outer Banks and Coastal Southeastern North Carolina", the briefing said.
"Just because you're not on the coast doesn't mean you won't get some big impact".
The time to prepare is nearly over, he said.
People fleeing coastal North and SC clogged highways as Florence bore down for a direct hit in the low-lying region dense with beachfront vacation homes.
"It truly is really about the whole size of this storm, " National Hurricane Center Director Ken Graham said.
As of 11 p.m., the storm was centered 280 miles southeast of Wilmington, North Carolina, moving northwest at 17 mph.
The massive storm is larger than North Carolina and South Carolina - combined, according to South Carolina Emergency Management. Reacting to the possibility of a more southerly track, Georgia Gov.
The strongest winds will occur where and when the storm makes landfall in a ring around the calm eye of the storm known as the eyewall. As it turns into southern SC.
He said hurricane-force winds extend outward 130 km from the center of the storm and tropical storm-force winds extend almost 322km out.
But the Miami-based NHC stressed it remained "a life-threatening situation" due to the risks of storm surge around coastal areas.
Farther from the epicenter, surges between 6-to-9 feet are expected near Myrtle Beach and Ocracoke Inlet.
More than 421,000 South Carolinians have already evacuated from the coast, McMaster said.
Numerous communities throughout the region have issued either mandatory or voluntary evacuation orders.
The rest of South and North Carolina as well as southwest Virginia may see up to 24 inches of rain. In North Carolina, Cooper says, "2,800 soldiers will be on active duty, joined by even more on standby".
"The Medical University of South Carolina Hospital says they are prepared to care for their patients". First off, additional weakening is unlikely until the eye comes ashore. Brian Wierzbicki, with U.S. Fleet Forces Command in Norfolk, Va. But one thing it might actually help is to reduce the overall wind speed, though we're still going to have gusty winds around here which combined with that wet soil could bring down some trees. Hurricane Florence's path is hitting many counties where fewer than 5% of people have flood insurance.
Florence should continue losing strength as it menders along the coast, weakening further as the storm travels across inland SC on Saturday, the weather service said.
While the storm may have slowed down slightly, it will still bring life-threatening storm surges, high winds, massive flooding and power cuts as it makes landfall on the coast of North and SC. "Catastrophic effects will be felt outside the center of the storm". Sustained winds remained at 90 miles per hour, but the storm - which was never expected to threaten the USA coast - should begin to weaken over the next day and become a tropical storm on Thursday, forecasters said in an 11 a.m. advisory.
"'This is not going to be a glancing blow".
U.S. television networks said 7pm to 7am curfews had been put in place in several towns surrounding Myrtle Beach. "The storm surge forecast associated with this storm has not changed". "It goes well inland".
"It will be historic", Baker said of the rain from Florence.
President Donald Trump both touted the government's readiness and urged people to get out of the way. "You can't stop Mother Nature".