The evacuation order for areas east of Interstate 95 and some areas to its west takes effect Saturday at 8 a.m., Deal said in a statement.
The order affects the cities of Savannah and Brunswick in Georgia, which has not been hit by a Category 3 hurricane or higher since 1898, according to WSB-TV.
"Ahead of Hurricane Irma, I've issued an executive order prohibiting price gouging and waiving rules and regulations for motor vehicles transporting supplies, equipment, personnel, goods and services associated with disaster assistance and relief", Deal said.
"It's too soon to know how North Carolina will exactly be impacted", Cooper said, "but it is not too soon to get ready for it".
Deal also expanded the state of emergency declaration from the six coastal counties to include 24 further inland. "Irma is a powerful storm".More news: La Liga chief accuses Paris Saint-Germain, Manchester City of "financial doping"
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Gov. Henry McMaster declared a state of emergency Wednesday, and while evacuations have not yet been ordered, residents along the coast have been told to prepare for that possibility.
State emergency officials said they don't want people to panic but want those in hurricane-prone areas to be prepared.
He stopped short of actually ordering a mandatory evacuation, but said those plans are based on the current information coming in on the projected path of Hurricane Irma and its potential impact on SC.
"We can't save you once the storm starts", said Scott.