Outer edges of Florence, now Category 1 storm, reach North Carolina with centre of hurricane expected to hit on Friday.

The outer reaches of Hurricane Florence began lashing coastal North Carolina with heavy winds and flooded roads on Thursday ahead of an expected landfall that will bring walls of water and lingering downpours to parts of the US East Coast.

The centre of Florence, which has been downgraded to a Category 1 storm, is expected to hit North Carolina’s southern coast on Friday, then drift southwest before moving inland on Saturday, enough time to drop as much as one metre of rain in some places, according to the National Hurricane Center.

An estimated 10 million people live in the storm’s path, according to the US Weather Prediction Center, and coastal businesses and homes were boarded up in anticipation. More than one million people had been ordered to evacuate the coasts of North and South Carolina and Virginia and thousands moved to emergency shelters, officials said.

Al Jazeera’s Jay Gray, reporting from Carolina Beach in North Carolina, said the situation is going to “intensify as the storm moves closer to the shore line”.

“In some areas, these conditions are going to continue for two days or more,” he said. “This is setting up to be a historic flooding in some of the low areas across the strike zone.”

Florence’s maximum sustained winds were clocked on Thursday at 165 kilometres per hour after it was downgraded to a Category 2 on the five-step Saffir-Simpson scale, according to the NHC. The winds had been as high as 140 miles per hour (roughly 225kph) earlier in the week.

But North Carolina Governor Roy Cooper warned: “Don’t relax, don’t get complacent. Stay on guard. This is a powerful storm that can kill. Today the threat becomes a reality.”

Some people who had rejected calls to evacuate the area in danger area took walks along the water as they tried to enjoy a few final hours of normalcy before Florence’s fury arrived.

In Sea Breeze, Roslyn Fleming, 56, made a video of the inlet where her granddaughter was baptised because “I just don’t think a lot of this is going to be here” after the storm, she told Reuters news agency.

Sixteen kilometres away in the city of Wilmington, wind gusts were stirring up frothy white caps into the Cape Fear River.

A man walks past a boarded-up business before Hurricane Florence comes ashore in Wilmington, North Carolina [Carlo Allegri/Reuters]

“We’re a little worried about the storm surge so we came down to see what the river is doing now,” said Linda Smith, 67, a retired nonprofit director. “I am frightened about what’s coming. We just want prayers from everyone.”