Gov. Henry McMaster has ordered mandatory evacuations for all coastal South Carolina counties starting at noon on Tuesday ahead of Hurricane Florence's projected landfall.

"The evacuation order will be inconvenient, but we do not want to sacrifice one South Carolina life, we are not going to gamble the lives of South Carolina people," McMaster said.

Click here to view the SC evacuation zones

Read: Hurricane Florence, Category 4 storm, driving 'life-threatening' conditions toward East Coast

McMaster also said in a news conference on Monday that officials will reverse the lanes on four big roads going away from the coast. All lanes on I-26 from Charleston to Columbia, Highway 501, Highway 278 and 21 in Buford County. All lanes will be reversed to lead away from the coast.

The 'flushing process' of the lane reversal will begin in Columbia at 8 a.m. on Tuesday as highway patrol clears I-26 to the I-526 interchange in Charleston. The lanes are expected to be fully reversed by Noon.

Highways will be reversed so everyone can get out, 'no one in.' McMaster said he's expecting a million people will evacuate.

South Carolina Emergency Management will open their emergency shelters on Tuesday based on need.

As of 5 a.m. Tuesday, Florence's winds were clocked at 140 mph with gusts of 165 mph. The center of the storm is about 410 miles south of Bermuda and 975 miles east-southeast of Cape Fear, North Carolina. The National Hurricane Center issued hurricane and storm surge watches for the entire Carolina coast, northward from Edisto Beach, South Carolina to the Virginia border.

In addition, public schools in 26 counties will be closed starting Tuesday. Click here to see a full list of counties.

Panovich said he expects Florence to approach the southeast coast on Thursday. Tropical storm force winds could be felt in Charlotte from this system. The Carolina coast needs to brace for impact Thursday and Friday. Even inland areas have the potential for Category 1 or 2 storms. Should Florence make landfall as a Category 4, it would be the first Category 4 hurricane since Hazel in 1954 to hit North Carolina.

Panovich said one thing to worry about is the storm slowing down as it approaches the Carolinas, which could lead to more flooding as the storm stalls out over the eastern half of the state.

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