Officials in North and South Carolina are imploring residents and visitors to evacuate ahead of Hurricane Florence, with more than 1 million expected to flee. The Category 4 storm is predicted to make landfall Thursday night, with tropical storm-force winds arriving by Thursday morning.

The focus now is on limiting the loss of life.

As of Tuesday morning, the center of the storm was in the Atlantic Ocean roughly halfway between Bermuda and Puerto Rico.

Mandatory evacuations were set to begin in eight coastal counties of South Carolina at noon Tuesday. Schools and government offices in coastal counties of both Carolinas have also been ordered closed.

The storm packed 140 mph winds Tuesday morning. The National Hurricane Center expected the storm to gain strength Tuesday “to near Category 5.”

‘We Are Bracing for a Hard Hit’

Gov. Henry McMaster of South Carolina said that the lanes of two major divided highways — Interstate 26 and U.S. 501 — would be reversed to make them one-way, carrying traffic only away from the coast for the mandatory evacuations starting at noon Tuesday, and that two other routes might also be reversed if needed. Schools and state offices in the lower half of the state will be closed.

“We know that this evacuation order I’m issuing is going to be inconvenient for some people,” the governor said. “We do not want to risk one South Carolina life in this hurricane.”

In North Carolina, Gov. Roy Cooper asked President Donald Trump on Monday to declare a federal state of emergency for his state. In coastal Dare County, the local emergency management agency announced a mandatory evacuation for all residents and visitors on Hatteras Island, the long, slender barrier island off the North Carolina coast, with a similar order to go into effect Tuesday for the rest of the county. Schools in 17 counties were expected to be closed Tuesday.

“The forecast places North Carolina in the bull’s-eye of Hurricane Florence, and the storm is rapidly getting stronger,” Cooper said. “When weather forecasters tell us ‘life-threatening,’ we know it’s serious. We are bracing for a hard hit.”

A Double Threat, Supercharged by Climate Change

Hurricane Florence presents a double threat to the region, said J. Marshall Shepherd, a meteorologist and professor of geography at the University of Georgia.

First, the coast faces high winds and storm surge from a powerful direct hit. But farther inland, he added, the probability of severe flooding is high if the storm stalls for several days once it makes landfall, as predicted. “The models are suggesting something very similar to what we saw with Harvey,” Shepherd said, referring to last year’s catastrophic flooding in Houston and elsewhere.

“This is another example of a one-two-punch storm,” he said. And although people generally prepare for coastal damage, they may underestimate the flooding threat.

“People have a hard time internalizing, preparing for something that’s outside their realm of experience,” he said. But Florence could bring conditions that people have not seen in their lifetimes. “It’s a dire situation that I believe is setting up,” he said.

Climate change is leading to more destructive storms in a number of ways, Shepherd noted. “When we have a storm like Florence, it’s certainly going to be shoving higher sea levels onto the coastline,” he said.

Although he said he was wary of linking individual storms to climate change, he added that scientific research laid out in authoritative documents like the National Climate Assessment of 2015 state that a warming climate increases the likelihood of “rainier storms,” with an increased risk of flooding.

Other scientific research suggests that Florence is part of the trend of storms affected by climate change. A 2014 study in the journal Nature shows a “poleward migration” of intense storms, and further research links climate change to a “wavier” jet stream, which could contribute to weakened steering currents, a phenomenon that kept Hurricane Harvey over Houston and could stall Florence over the Carolinas, as well.

Schools and Government Offices Closing

Schools were scheduled to close Tuesday in large swaths of North and South Carolina, with many of them set to serve as shelters for people fleeing the hurricane.

In South Carolina, McMaster issued an executive order Monday closing all state offices and public schools, including state colleges, universities and technical colleges, in 26 counties threatened by Hurricane Florence. The closings would affect more than 430,000 students in kindergarten through high school, said Ryan Brown, a spokesman for the state education department.

Schools on higher ground that have been designated as shelters will be serving food and staffed by the American Red Cross and other relief workers, he said.

Although South Carolina schools are experienced at dealing with hurricanes, this one is expected to be the most challenging the state has seen in a long time, Brown said. “This is the strongest hurricane we’ve had since Hurricane Hugo in 1989. That was a direct hit to Charleston, Category 4.”

In North Carolina, schools in 17 eastern counties were expected to close, said Graham H. Wilson, a spokesman for the state’s department of public instruction. Most of those closures were set to begin Tuesday, but some were scheduled for Wednesday and the timing of others was still to be announced.

“We do anticipate more closings, once the path and severity of the storm is more certain,” Wilson said.

This article originally appeared in The New York Times.

Richard Fausset © 2018 The New York Times