Add Hurricane Florence as an interest to stay up to date on the latest Hurricane Florence news, video, and analysis from ABC News.
The slow-moving storm, the most severe hurricane to threaten the USA mainland this year, was rated a Category 4 on the five-step Saffir-Simpson scale and located about 845 miles (1,360 km) east-southeast of Cape Fear, North Carolina, at 1:30 p.m. EDT (1730 GMT), according to the NHC.
The storm weakened slightly and has 130 miles per hour winds, but it is still a major Category 4 hurricane, according to the Saffir-Simpson Hurricane Wind Scale.
Tropical expert Dr. Jeff Masters of Weather Underground lays out a potentially catastrophic storm surge scenario for Florence and the Carolinas pointing out the devastating nature of the storm surges produced by two of the three CAT 4 strength hurricanes which have hit the coastline north of Georgia at high tide since 1851: Hurricane Hazel on October 15, 1954 and Hurricane Hugo on September 22, 1989.
South Carolina's governor ordered the state's entire coastline to be evacuated starting at noon on Tuesday.
Officials in both North and SC are urging citizens to evacuate inland, especially those living in low-lying or coastal areas.
According to AccuWeather there is a potential scenario where Florence will stall or significantly reduce its speed which could prolong the effects of damaging winds, storm surge flooding and beach erosion.
On its current track, Florence is expected to slam South Carolina, North Carolina and Virginia the hardest.
The US capital declared a state of emergency Tuesday as Hurricane Florence bears down on the US East Coast, threatening torrential rain and flooding in the Washington region. Storm surge may be more than 10 feet in these areas, according to ADCIRC, a computer model developed over 30 years by the University of Notre Dame and University of Texas. The Carolinas and Virginia have already issued evacuations in coastal areas.
National Hurricane Center Director Ken Graham warned that Florence was forecast to linger over the Carolinas once it reaches shore.
All signs pointed to a stronger, slower, wider and wetter hurricane in the days ahead, forecasters said.
A long recovery is predicted for the states after the major hurricane hits. "Florence has rapidly intensified into an extremely unsafe hurricane", Blake wrote Monday evening that top sustained winds would approach the 157 miles per hour (253 kph) threshold for a worst-case Category 5 scenario. The forecast is for landfall to occur overnight Thursday into Friday morning.
"It is an extremely risky, life-threatening, historic hurricane".