"We may not even get the worst of it until Saturday", Sharp said. Ahead of what is projected to be massive devastation for several Southeast states, NASA has released high-definition footage of the storm as viewed from the International Space Station above the Atlantic Ocean.
The Weather Prediction Center tweeted a version of the same seven-day rainfall forecast.
Meteorologists are warning of potentially catastrophic flooding in the area, with isolated amounts of up to 40 inches of rain expected in parts of SC.
"When people face the decision to leave their homes or stay and fight the storm, having the option to safely store their belongings can make that decision easier", Mack said.
The storm, which is building up over the Atlantic, is due to make landfall in either North or SC within the next few days, and is expected to be the worst storm to hit the area in 30 years.
Meanwhile, some of North Carolina's 2,100 industrial-size hog farmers are scrambling to drain waste pools containing manure before the hurricane hits, according to NPR.More news: Turkey Is Responsible for Separating out Islamists in Syria, Russian Envoy Says
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Hurricane Florence intensified to a Category 4 hurricane on Monday as it barreled towards the US East Coast, where millions of people are bracing for potentially devastating winds and water later this week.
No storm watches or warnings are in effect for Georgia, but forecasters warned that the monster storm could hesitate just offshore for days - punishing a longer stretch of coastline harder than previously feared - before pushing inland over the weekend.
President Donald Trump declared a state of emergency for all three states, with Florence likely to bring widespread flooding and destruction once it arrives.
"The focus should be on the potential for torrential downpours that will lead to potentially life-threatening flooding", said meteorologist Scott Sharp. It's big and it's vicious.
He added: "The waves and the wind this storm may bring is nothing like you've ever seen".
Some 38cm (15in) to 64cm (25in) of rain is forecast in some areas - with up to one metre (40in) at the centre of the storm.
The alerts also mean risky storm surges are likely along the coast and heavy, sustained rains could cause life-threatening flooding inland, the National Hurricane Center warned.