COLUMBIA, S.C. – Just one hour after the National Hurricane Center upgraded Matthew to a category 4 storm, South Carolina Governor Nikki Halley ordered an evacuation of coastal areas in Horry and Georgetown counties.

During a 10 a.m. press conference Thursday, Haley said the evacuations would begin at noon. On Wednesday, state officials reversed lanes on I-26 leaving Charleston in an effort to speed up the evacuation process.

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Haley said the lane reversals worked “beautifully” and thanked the state patrol, National Guard, and local governments for working together in a timely fashion. According to Haley, the average travel time from Charleston to Columbia was just under 90 minutes. But Haley wasn’t entirely pleased with the process, saying too many people hadn’t evacuated the area.

“As of 6 a.m., 175,000 people have evacuated,” Haley said. “That’s not enough. We need to have more people evacuating.”

Haley stressed to those who were considering staying that resources would be almost zero in the coming days.

“If you are still sitting at home, if you haven’t evacuated, gas stations are getting ready to close. Your pharmacies are getting ready to close,” Haley said. “You will not have access to gas stations, pharmacies, or any stores.”

State officials say that evacuees leaving the coastal area should pack the following essential items: required medications, adequate clothing and essential personal items.