Florida, South Carolina on high alert as Hurricane Matthew tears through Caribbean

As Hurricane Matthew barreled up the Caribbean Wednesday, people along the Atlantic coast from Florida to South Carolina prepared to move to safer ground, as officials warned that hundreds of thousands of people would have to evacuate.

South Carolina Gov. Nikki Haley announced plans starting Wednesday afternoon to evacuate a quarter million people, not counting tourists, from its vulnerable coastline. Officials in central Florida's Brevard County on Wednesday ordered residents on barrier islands and in flood-prone areas to pack up and get out.

Florida Gov. Rick Scott said his state could see its biggest evacuation ever. "If you're able to go early, leave now," he added.

Matthew was a dangerous and life-threatening Category 3 storm with sustained winds of 120 mph, and it was expected to be very near Florida's Atlantic coast by Thursday evening.

At 8 p.m. EDT, Matthew was centered about 165 miles south-southeast of Nassau in the eastern Bahamas. It was heading northwest at 12 mph.

Hurricane-force winds extended outward up to 45 miles from the center, meaning Matthew could wreak havoc along the East Coast even if it did not actually come ashore.

President Barack Obama was briefed on the federal government's preparations Wednesday. He told reporters that now is the time to "hope for the best but we want to prepare for the worst."

Traffic was bumper-to-bumper during morning rush hour on Interstate 26 in South Carolina as people tried to escape ahead of the storm. Gasoline was hard to come by, with at least half a dozen stations in Mount Pleasant out of fuel and lines at others.

At one gas station in Mount Pleasant, the line reached about a quarter mile down the street. The state's attorney general warned stations against price gouging.

According to Fox Carolina, Greenville County schools weren’t going to run buses Wednesday for students and instead drivers would be sent to the coast to help evacuate residents. Students expecting buses and have no other mode of transportation would be excused.

In South Florida, government officials are worried residents have become complacent after 11 years of near misses. Hurricanes Wilma and Katrina along with Andrew were in the mind of officials as they spoke at a press conference Tuesday. Rep. Carlos Curbelo wants assurances that the federal, state and local governments are working together.

"We just can't take it for granted that that's always going to happen," Curbelo said.

From Broward County to the Space Coast -- where hurricane warnings are in effect -- officials already have closed schools for the rest of the week. Some school districts are sending students home early on Wednesday, and after school activities are canceled. Most colleges and universities in the warning areas also have canceled classes starting Wednesday evening.

A hurricane watch is in effect from Sebastian Inlet to the Daytona Beach area, meaning hurricane force winds could occur.

In South Florida, lines at grocery stores were heavier than usual and some essentials were in short supply. When Simone Corrado and her husband tried to buy water at their Publix in Davie near Fort Lauderdale, they mostly found empty shelves. There were a few bottles of high-end water brands, but there was so much empty shelf space that Corrado lay down and fully stretched out on the bottom shelf.

"I got scared because all that was left at Publix was just the pricey water," said Corrado, who lived through 1992's catastrophic Hurricane Andrew, which practically leveled the nearby city of Homestead. "They really put the fear into you here. On the television screen every few minutes is the 'beep, beep, beep' storm alert."

Governors in Florida, Georgia, South Carolina and North Carolina declared states of emergency, and the White House said President Barack Obama canceled a campaign and health care events in Florida on Wednesday and would instead visit the headquarters of the Federal Emergency Management Agency for an update.

Some airlines let passengers change travel plans without penalty if their trip might be affected by Matthew.

Near Fort Lauderdale, The Home Depot in Davie briefly ran out of propane for gas barbecues and the supply of batteries was dwindling. People bought plywood to cover windows, tarps to put over outdoor furniture and coolers for food storage.

Anesthesiologist Darby Lipka lugged a 20-pound propane tank across the parking lot, saying he had already purchased food and water. He installed hurricane windows years ago so he wouldn't need to erect shutters

"I am just trying to be prepared," he said.

Haley said state officials would reverse lanes on major evacuation routes in South Carolina. It would be the first major evacuation since Hurricane Floyd in 1999, when the governor at the time didn't reverse the lanes and Interstate 26 became a parking lot. A typically two-hour drive from Charleston to Columbia turned into 24-hour nightmare.

The National Hurricane Center in Miami said Matthew — recently a Category 4 storm and at one brief point a fierce Category 5 — will remain a powerful storm at least through Thursday night. It added that while maximum winds decreased slightly in recent hours, further fluctuations in intensity are possible in coming days.

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The Associated Press contributed to this report.