Hurricane Florence, from which tropical-storm-force winds are extending almost 200 miles, has begun pounding the Carolina coastline as officials make last-minute pleas for residents to evacuate.
Officials warn of life-threatening storm surges in North and South Carolina as the hurricane moves towards land with maximum sustained wind speeds of 90mph (150 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 told to leave.