Winds will continue to increase throughout the day and will remain strong for much of Saturday.
A gust of 169km/h was recorded at Wilmington airport, surpassing the power of Hurricane Fran two decades ago.
Florence made landfall as a Category 1 hurricane at 7:15 am at Wrightsville Beach, a few miles east of Wilmington and not far from the SC line, coming ashore along a mostly boarded-up, emptied-out stretch of coastline.
North Carolina Governor Roy Cooper warned that "disaster is at the doorstep" and pleaded with residents and tourists alike not to underestimate the threat to life Florence poses. By that time, emergency crews had already been deployed to parts of the state where people were trapped by floodwaters.
North Carolina alone is forecast to get 36 trillion litres, enough to cover the North Carolina to a depth of about 25 cm.
Meteorologist Ryan Maue of weathermodels.com said Florence could dump a staggering 68 trillion litres of rain over a week on North Carolina, South Carolinas, Virginia, Georgia, Tennessee, Kentucky and Maryland.
Airlines canceled more than 2,100 flights through Sunday. North of the landfall, another 150 people near the town of New Bern required rescue from floods along the Neuse River.
Hurricane Florence has killed at least three people after it crashed on North Carolina's coast on Friday.
According to radar images as of 7 a.m., the storm's eye was drawing near the New Hanover-Pender County line.
"I have no generator", said Petra Langston, a nurse.
As Hurricane Florence barreled into the shores of Wrightsville Beach, N.C., early Friday, Americans braced for destruction that will effectively shut down daily life across the Southeastern United States in the coming days.
The wind howled and sheets of rain splattered against windows of a hotel before dawn in Wilmington, where Sandie Orsa of Wilmington sat in a lobby lit by emergency lights after the power failed.
Reports out of Wilmington, North Carolina, said that the outer bands of wind and rain from Florence, a Category 2 storm with 105 miles per hour winds, are hitting North Carolina.
As Hurricane Florence crashed onto the Carolinas, federal emergency teams prepared themselves to work on a long process of rebuilding the storm-battered landscape it would leave behind.