Though it was downgraded to a Category 1 hurricane at landfall Friday, Florence remains a massive storm that will dump trillions of gallons of rain on eastern North Carolina before sweeping across SC.
The National Hurricane Center says the high winds - combined with rain-soaked soil - will cause many trees to fall in coming days, crashing into homes, streets and onto power lines.
The massive system weakened into a tropical storm in the late afternoon but across the region, emergency officials warned that more water was yet to come, with cresting rivers and flash flooding fed by the unending rain.
With one grueling day behind them, the Carolinas on Friday grappled with rising water and cascading misery from a deadly and agonizingly slow-moving Tropical Storm Florence expected to linger through the weekend.
Florence drove almost 1 million people from their homes and almost 700,000 lost power.
Nearly 800,000 people are reported to be without power already in North Carolina, and officials have warned restoring electricity could take days or even weeks.
Florence acquired a Category 4 major hurricane status with estimated maximum sustained winds of 215km/h on 4 September.
Rescue crews in Onslow County helped evacuate 70 people from a Jacksonville hotel early Friday after the roof collapsed and rain rushed in.
More ominously, forecasters said the onslaught on the coast would last for hours and hours because Florence had come nearly to a dead halt at just 3 mph (6 kph) as of midday. However, there is still some disagreement among the models as to how much of the storm center motion is to the north vs. the northeast. Forecasters said this onslaught could last for days, leaving a wide area under water from both heavy downpours and rising seas.
Screaming winds bent trees and raindrops flew sideways as Florence's leading edge battered the Carolina coast Thursday. About 210,000 people were staying in 170 shelters in the Carolinas.
Parts of West-central Virginia and far eastern West Virginia will see "life-threatening flash flooding and river flooding, along with an elevated risk for landslides", according to the agency.
Calls for help multiplied as the wind picked up and the tide rolled in.
Since making landfall at Wrightsville Beach in North Carolina on Friday morning, Florence's forward speed has slowed down dramatically, with the storms center of circulation only about 100 miles away from Wrightsville Beach a full 24 hours after landfall.
In New Bern, North Carolina, the storm surge overwhelmed the town of 30,000, located at the confluence of the Neuse and Trent rivers. Gusts reached over 100 miles per hour - the highest recorded in North Carolina since 1958.
The storm's movement, not its strength, has forecasters and officials anxious.
Blowing ashore with howling 155 km/h winds, Florence splintered buildings, trapped hundreds of people and swamped entire communities along the Carolina coast Friday in what could be just the opening act in a watery, two-part, slow-motion disaster.
As Florence drew near, President Donald Trump tweeted that FEMA and first responders are "supplied and ready", and he disputed the official conclusion that almost 3,000 people died in Puerto Rico, claiming the figure was a Democratic plot to make him look bad. "And you don't need power to sling booze", said owner Eli Ellsworth. "Really all you could do is stay inside and hope for the best".