Four major roads will reverse their traffic lanes to help facilitate the mass exodus.
As coastal communities up and down the East Coast prepare for the worst this weekend from Hurricane Florence, Massachusetts need not join them in filling up sandbags and stocking up on bottled water. "This may be inconvenient".
The evacuation order extends to eight counties along the state's coast, with McMaster estimating that around one million people - residents and visitors - will be affected by the order. Eastbound lanes of Interstate 26 heading into Charleston and US 501 heading into Myrtle Beach will be reversed when the order takes effect. That means, she said, that the Wilmington region is going to be affected by what she said is going to be a major hurricane that could reach category 4 strength, which means maximum sustained winds of 130 to 156 miles per hour. The storm is already 500 miles wide - meaning a large area will be at risk when it nears land.
"Interests in the Lesser Antilles should continue to monitor Isaac during the next few days".
Meteorologists are forecasting that Florence will continue to pick up speed before making its landfall between SC and North Carolina on Thursday as a category 3 or higher hurricane.
He said: "For most of the people who live here, this storm is likely to be nothing like they have ever experience before".
"On the forecast track, the center of Florence will move over the southwestern Atlantic Ocean between Bermuda and the Bahamas Tuesday and Wednesday and approach the coast of SC or North Carolina on Thursday".
As Hurricane Florence heads toward the East Coast, two other storms are bringing up the rear - Helene and Isaac. In September of 1998 there were 4 hurricanes in the Atlantic at the same time. By evening, the storm was centered about 1,170 miles (1,880 km) east-southeast of Cape Fear, North Carolina, the NHC said.
This next map may give you a better idea of when to first expect to feel the effects of the hurricane.
The storm "is too powerful and its path is too uncertain to take any chances", South Carolina Governor Henry McMaster said in issuing his state's emergency declaration.
Latest forecasts have Florence making landfall in the vicinity of Wilmington, North Carolina Thursday evening/night.