Officials warn of life-threatening storm surges in both North and South Carolina as the hurricane moves towards land with maximum sustained wind speeds of 100mph (155 km/h).
More than 100,000 homes are already without power as weather conditions begin to worsen.
Officials have warned the storm has the potential to kill "a lot of people" amid risks of "catastrophic" flooding.
More than a million people along the coastlines of North Carolina, South Carolina and Virginia have been ordered to evacuate.
Thousands had taken shelter in emergency facilities by Thursday night.
Photographs showed residents crowded into corridors with blankets on inflatable mattresses and mats.