President Barack Obama has declared a state of emergency in Florida as potentially catastrophic Hurricane Matthew approaches.
Hurricane Matthew remains a Category 4 storm with winds of 140 mph, according to the latest National Hurricane Center advisory.
As of 2 p.m. ET, Matthew was located about 125 miles east-southeast of West Palm Beach, Florida, and is expected to make a northwest turn toward the peninsula sometime Thursday night or early Friday.
Here's what you need to know now about the powerful storm that forecasters say is gaining strength:
• The storm has already killed at least 113 people in three Caribbean countries. The overwhelming majority, 108 people, died in Haiti, said Civil Protection Service spokesman Joseph Edgard Celestin.
• Hurricane Matthew has strengthened into a Category 4 hurricane with winds of 140 mph and gusts up to 165 mph, according to the National Hurricane Center. Matthew continues to head toward Florida's east coast and is expected to hit the coast late Thursday or early Friday. As of 11 a.m. ET, it was located about 180 miles southeast of West Palm Beach and was moving northwest at 14 mph.
• Daytona Beach, Florida, Mayor Derrick Henry told CNN he fears residents might be emboldened by the fact that his city hasn't seen a direct hit from a hurricane in four decades. "We're not immune. ... Get out. That is our message and that is our hope. Worry about your possessions later. Take care of your life now. You only have one life," he said. St. Augustine Mayor Nancy Shaver issued a similar warning.
• Authorities urged more than 2 million people to leave their homes in coastal Florida, Georgia and South Carolina as the storm neared -- the largest mandatory evacuations in the United States since Hurricane Sandy hit the East Coast in 2012.
• Based on the latest projections, Matthew could make landfall in Florida as a Category 4 hurricane. It could also skirt the coast as it continues north. While Matthew's outer bands were already starting to hit Miami-Dade County by mid-morning, Mayor Carlos Jimenez said there's a bit of good news: "The probability of sustained hurricane winds has gone down 13%." The latest advisory says hurricane-force winds will extend 60 miles from Matthew's eye, while tropical storm force winds will impact areas 160 miles from the eye.
• Florida Gov. Rick Scott offered a dire warning Thursday morning for people living in evacuation zones: "This is serious. ... If you need to evacuate and you haven't, evacuate. This storm will kill you. Time is running out. We don't have that much time left."
Officials at Walt Disney World, Universal Studios and SeaWorld say they'll be shutting down until the storm passes.
Disney officials said on the company's website Thursday afternoon that theme parks, water parks, Disney Springs, the miniature golf course and the ESPN Wide World of Sports Complex would close at 5 p.m. The theme park will remain closed through Friday.
Alyson Lundell is director of public relations for Universal Orlando. She said in a statement that Universal Studios Florida, Universal's Islands of Adventure and Universal Citywalk would close at 5 p.m. and remain closed on Friday.
Earlier Thursday, SeaWorld announced on its website that the park would close at 2 p.m. and remain closed on Friday.
Florida braces for direct hit
Gov. Scott warned 1.5 million residents not to take evacuation orders lightly, telling Floridians on the state's east coast the question is not whether they will lose power, but for how long.
"There is no reason not to evacuate," he said. "No one should be taking any chances."
A direct hit by Matthew, he said, could lead to "massive destruction" on a level unseen since Hurricane Andrew devastated the Miami area in 1992. Voluntary and mandatory evacuations in his state stretch from the Miami area all the way north to the Florida-Georgia border.
People who stayed behind stocked up on supplies and boarded up windows. Throughout Thursday, reports began flowing in of county governments, schools and amusement parks across the state closing. Many residents found long gas lines Wednesday. But so far, the state isn't running short on supplies, Scott said.
Airline passengers were urged to call before leaving for the airport. As of mid-morning, Florida airports had canceled almost 1,400 flights, most of them at Miami, Fort Lauderdale and Orlando. Fort Lauderdale has closed it airport, while Orlando is slated to close at 8 p.m., airport officials said.
Palm Beach residents cleared many grocery store shelves ahead of the storm. Yet despite all the warnings, West Palm Beach Mayor Jeri Muoio said not everyone is listening, even with mandatory evacuation orders in place.
"More people are staying than leaving. It's very concerning. When the winds really pick up, we will not be sending people out," she said.
Muoio added, "Here's the problem: You don't evacuate. It gets bad. Now you decide, 'Now I want to evacuate.' It's too late. You dial 911. You want to get rescued. We can't come to you. It's too dangerous. ... You're actually putting responders at risk to save you in the worst part of the storm."
In Jupiter, resident Randy Jordan told CNN affiliate WPEC people were pushing and shoving their way through the local Home Depot to buy supplies ranging from batteries to flashlights.
Mandatory evacuations in South Carolina
Cars packed highways in South Carolina, where officials gave mandatory evacuation orders for several counties.
So far, about 250,000 people have left the area. And as many as 200,000 people will leave Thursday, said Kim Stenson, the director of South Carolina Emergency Management.
Tempers apparently flared during the slow traffic. A man got out of his truck at a point where vehicles were being redirected, removed a traffic cone and sped away. Police chased the man until he stopped on a dead-end road. The man fired at deputies and police officers, who shot back and wounded him, Berkeley County Chief Deputy Mike Cochran told CNN. The man was hospitalized, but his condition is unknown.
The South Carolina Department of Transportation changed the directions of eastbound traffic lanes to accommodate the exodus of people leaving coastal cities like Charleston.
As thousands fled inland, some people said they were staying put. Charleston residents boarded up businesses and prepared to hunker down.
Cheryl Quinn said she and her husband were fine a year ago when Charleston endured heavy rain after a brush with a big storm.
"It was kind of a party down here. I hate to say that," she said, but she's reserved a hotel room, just in case.
North Carolina playing it by ear
North Carolina Gov. Pat McCrory declared a state of emergency for more than half the state's 100 counties. So far, though, the governor has not urged residents to evacuate.
"We're just going to have to play it by ear and have our resources ready," the governor said.
Officials are still concerned areas in eastern North Carolina that were recently flooded will see drenching rains from Matthew.
Georgia governor: 'Remain calm, be prepared'
Georgia Gov. Nathan Deal has declared a state of emergency in 30 counties on or near the Atlantic Coast and ordered evacuations for several counties, all on the coast, east of Interstate 95.
Of special concern is Tybee Island, a low-lying island east of Savannah, which is also under mandatory evacuation orders.
"Remain calm, be prepared and make informed, responsible decisions," Deal said.
In Savannah, Mayor Eddie DeLoach warned those who stay that they'd be on their own.
"Hurricane Matthew is a storm not to be messed with. If you decide to ride it out, do not expect us to be there to help you. We will not risk the lives of our emergency responders to save those who refused to heed this evacuation call," he said in a statement.
Meanwhile, CNN affiliate WSB reported 20-mile long traffic backups on I-75 northbound, south of metro Atlanta, as people from coastal areas sought to flee the storm.