Hurricane Florence has made landfall on the US East Coast, knocking out power to half a million homes and causing buildings to crumble.
The centre of the storm struck Wrightsville Beach in North Carolina, with gales of up to 90mph (150 km/h).
Rains and surging seas have already inundated coastal areas. Dozens of people were rescued from a collapsing hotel in North Carolina overnight.
Evacuation warnings are in place for 1.7 million people.
North Carolina Governor Roy Cooper said surviving the storm would be a test of “endurance, teamwork, common sense and patience”.
“This is an uninvited brute that just won’t leave,” he told NBC on Friday.
National Weather Service forecaster Brandon Locklear said North Carolina is likely to see eight months of rain in two to three days.
Thousands of miles away, meanwhile, a huge typhoon is moving towards the Philippines. More than five million people are in the path of Super Typhoon Mangkhut, officials say.
Conditions deteriorated on Friday as slow-moving Hurricane Florence crawled along at 6mph (9.5km/ h).
Its wind speeds had lowered slightly on Thursday night, making it a category one hurricane.
But the National Hurricane Center says the tempest remains extremely dangerous because of the high volume of rainfall and predicted storm surges.
By Friday morning, the North Carolina coastal town of Atlantic Beach had already received 30in (76cm) of rain, the US Geological Service said.
The storm is forecast to dump about 18 trillion gallons of rainwater on US soil, most of it in North Carolina, meteorologist Ryan Maue tweeted.
Hurricane Harvey last year dumped some 33 trillion gallons of rainwater in the US.
More than 497,000 homes and businesses are already without power, and energy companies warn up to three million homes and businesses could lose electricity.
Officials have warned restoring electricity could take days or even weeks.
In Jacksonville, North Carolina, officials rescued about 60 people overnight from a hotel that was collapsing in the storm.
Emergency workers arrived to find the Triangle Motor Inn’s structure crumbling, with many guests still in their rooms.
As parts of the roof caved in, police had to force their way into some rooms amid 75mph winds to reach those inside.
All of the occupants, who included children and pets, were safely rescued.
More than 20,000 people are meanwhile taking refuge in emergency shelters.
Parts of New Bern, North Carolina, are 10ft (3m) underwater and householders were waiting to be rescued, authorities there said.
New Bern Police Lieutenant David Daniels said on Friday morning that between 150 and 200 people had been plucked to safety.
Local resident Peggy Perry told CNN she was “stuck in the attic” along with three relatives in her New Bern home.
“In a matter of seconds, my house was flooded up to the waist, and now it is to the chest,” she added.
Officials have warned against entering attics, unless people have a means to cut through to the roof to avoid drowning.
Over 1,100 flights have been cancelled, according to FlightAware.com, as most of the coastal region’s airports are closed to ride out the storm.
At the White House, President Donald Trump has been retweeting local emergency officials’ updates and tips for surviving the storm.
Latest predictions show the storm slowing to a near standstill as it pummels the coast with “copious amounts of rain” from Thursday night to Saturday.
Wind speeds are only expected to weaken on Saturday as the storm moves slowly across land.
More than a dozen counties in North Carolina are under a tornado watch, with officials also warning of a chance of hail.