The surge won't be as bad as it potentially could have been, however, and the winds won't be as strong. "Your time is running out". "We will have catastrophic effects".
The National Hurricane Center warned the threat of tornadoes was increasing as Florence neared shore and South Carolina Governor Henry McMaster said the heavy rains could trigger landslides in the western part of his state.
Life-threatening storm surges of up to 13 feet have been forecast in some areas when the monster storm eventually makes landfall in North and SC. Widespread rainfall amounts could reach 152mm to 300mm, spurring flooding.
Persistent rains with 160 km/h winds or higher will take their toll on structures.
Florence has weakened a bit over 24 hours, but it's also grown even larger - and it will likely dump torrential rain over North and SC through Monday.
But what forecasters are keeping an eye on, in particular, is the forward motion of the storm.
Weather Underground meteorology director Jeff Masters said Florence eventually could strike as a Category 1 hurricane with winds less than 160 kph, but that could still cause at least $1 billion in damage.
Hurricane warnings are in effect for the South Santee River in SC to Duck, North Carolina, and Albemarle and Pamlico sounds. This website is not intended for users located within the European Economic Area. A tropical storm warning covers the area from north of Duck to the Virgina Tidewater area.
About 10 million people live in the path of the slow-moving storm and more than 1 million had been ordered to evacuate the coasts of the Carolinas and Virginia, jamming westbound roads and highways for miles.
Robinson noted that some of the forecasts are expecting rainfall of 800 to 1000 mm over a 30-hour period.
The U.S. Naval Forces North Command also has deployed ships off the S.C. coast once the storm passes for recovery and rescue efforts, should support be needed, said Lt. Cmdr. The Weather Channel reported the storm is likely to make landfall either tonight or Friday, after which it will stall over the Southeast, producing buckets of rain that could accumulate to unsafe amounts.
"Think of it like a marathon", said Mark Robinson, from The Weather Network, also in Wilmington with Kourounis. North and SC already faced flooding earlier this summer. The Charleston area is under a storm surge watch.
Forecasters' European climate model is predicting two trillion to 11 trillion gallons of rain will fall on North Carolina over the next week, according to meteorologist Ryan Maue of weathermodels.com.
The Carolinas will bear the brunt of the storm, but as it moves inland, Virginia, Georgia, and Maryland will also be hit.
Florence is one of four named storms in the Atlantic. If the storm makes landfall as a Category 2, these winds will be damaging, sustained at up to 160km/h or so with higher gusts. The biggest problem will likely be mass power outages, he says.
Paige Sheehan, a spokesperson for local utility Duke Energy, told us on Wednesday that the company had 20,000 workers at the ready to restore power, but that it was warning customers they could be without power for weeks. "The larger and the slower the storm is, the greater the threat and the impact - and we have that". It's now predicted to make landfall near Wilmington and then head west across SC. Then they can assess the damage and begin the restoration process.