Florence has already inundated coastal streets with ocean water and forecasters say that "catastrophic" freshwater flooding is expected along waterways far from the coast of the Carolinas. A frankly terrifying reminder, at that.
It's not all for show, either. "We can not underestimate this storm".
Port Canaveral along Florida's Space Coast had two ships visiting unexpectedly when Hurricane Florence made it impossible to stop in Bermuda.
Up to 10 million people lie in the path of the storm, which still poses a risk to life and property, although it has been downgraded to a Category 2 hurricane.
But North Carolina Governor Roy Cooper warned: "Don't relax, don't get complacent".
Flooding from heavy rains is the second-leading cause of fatalities in tropical storms and hurricanes that make landfall.
It's unclear exactly how many people fled ahead of the storm, but more than 1.7 million people in the Carolinas and Virginia were warned to clear out.
Florence's center will approach the North and SC coasts late Thursday and Friday.
Florence's weakening as it neared the coast created tension between some who left home and authorities who anxious that the storm could still be deadly.
The total bill for damage from Florence could eventually reach $US10 billion ($13.8b) to $US20 billion ($27.7b), said Chuck Watson, a disaster researcher at Enki Research in Savannah, Georgia.
While Florence's winds won't be as intense as first feared, the storm could dump as much as 3 feet of rain and generate storm surges as high as 13 feet in coastal areas, the weather service said.
The rain has turned sideways, rivers are swollen and flood waters are swamping streets as the fury of Hurricane Florence threatens the Carolina's with life-threatening conditions. GOES-East is one many satellites in orbit tracking the hurricane as it approaches the Carolinas. When fierce winds keep up for a long time, homes are "going to start to deteriorate".
More than 60 people had to be pulled from a collapsing motel at the height of the storm, and many more who defied evacuation orders were hoping to be rescued.
Hurricane Florence is a real, ongoing threat.
Airlines have cancelled more than 1,500 flights, and coastal towns across the Carolinas are largely empty after 1.7 million people in three states were told to clear out. Millions were expected to lose power from the storm and restoration could take weeks. Most of the damage during Hurricane Matthew in 2016 in North Carolina came from inland flooding - 31 people died and almost 100,000 homes were destroyed.
The expected high winds and slow movement of the hurricane as it comes ashore are likely to make rescue efforts in flooded areas challenging, senior US Defence Department officials say.
"When that last ferry pulls out.it's unnerving to see it pull away and know, 'That's the last chance I have of getting off this island, '" she said Wednesday.