Hurricane Florence, on track to become the first Category 4 storm to make a direct hit on North Carolina in six decades, howled closer to shore on Tuesday, threatening to unleash deadly pounding surf, days of torrential rain and severe flooding.

Fierce winds and massive waves are expected to lash the coasts of North and South Carolina and Virginia even before Florence makes landfall by early Friday, bringing a storm surge as much as 4 meters, the National Hurricane Center in Miami warned. Catastrophic floods could follow if the storms talls inland, it says.

Although Florence was still days from arrival, authorities took extraordinary measures to move people out of harm’s way. More than 1 million residents have been ordered to evacuate from the coastline of the three states, while university campuses, schools and factories were being shuttered.

The US Coast Guard closed ports in Wilmington and Morehead City, North Carolina and Hampton Roads, Virginia to inbound vessels greater than 500 tons and was requiring vessels of that size to leave if they did not have permission to be in the ports.

Packing maximum sustained winds of 225km per hour, the storm ranked as a Category 4 on the five-step Saffir-Simpson hurricane scale and was expected to grow stronger and larger over the next few days, the NHC says.

“This storm is a monster,” North Carolina Governor Roy Cooper says. “Even if you’ve ridden out storms before, this one is different. Don’t bet your life on riding out a monster.”

He cited forecasts showing Florence was likely to stall over North Carolina, “bringing days and days of rain.”

To hasten evacuations from coastal South Carolina, officials reversed the flow of traffic on some highways so all major roads led away from shore.

Kathleen O’Neal, a resident of Ocracoke Island in North Carolina’s Barrier Islands, said she, her husband and son would ride out the storm. “A lot of local people are staying,” she said of the island, which is reachable only by ferry or plane.

Maps of Florence’s trajectory showed its center most likely to strike the southern coast of North Carolina. The last Category 4 hurricane to plow directly into North Carolina was Hazel in 1954, a devastating storm that killed 19 people and destroyed some 15 000 homes.