TALLAHASSEE, Fla. (AP) -- An estimated 120,000 people along the Florida Panhandle were ordered to clear out on Tuesday as Hurricane Michael rapidly picked up steam in the Gulf of Mexico and closed in with winds of 110 mph and a potential storm surge of 12 feet.
Beach dwellers rushed to board up their homes and sandbag their properties against the fast-moving hurricane, which was expected to blow ashore around midday Wednesday.
The speed of the storm — Michael was moving north 12 mph (19 kph) — gave many people a dwindling number of hours to prepare or flee before being caught up in damaging wind and rain.
"Guess what? That's today," National Hurricane Center Director Ken Graham said. "If they tell you to leave, you have to leave."
By 11 a.m., Michael had winds of 110 mph (175 kph), just below a major Category 3 hurricane, and was getting stronger, drawing energy from Gulf waters in the mid-80s.
The hurricane's effects will be felt far from its eye.
Forecasters said Michael's tropical storm-force winds stretched 370 miles (595 kilometers) across, with hurricane-strength winds extending up to 35 miles (55 kilometers) from the center.
Florida Gov. Rick Scott also warned people across northwest Florida that the "monstrous hurricane" was just hours away, bringing deadly risks from high wind, storm surge and heavy rain.
His Democratic opponent in Florida's Senate race, Sen. Bill Nelson, said a "wall of water" could cause major destruction along the Panhandle.
"Don't think that you can ride this out if you're in a low-lying area," Nelson said on CNN.
Mandatory evacuation orders went into effect for some 120,000 people in Panama City Beach and across other low-lying parts of the coast.
Forecasters said parts of Florida's marshy, lightly populated Big Bend area — the crook of Florida's elbow — could see up to 12 feet (3.7 meters) of storm surge.
Michael also could dump up to a foot (30 centimeters) of rain over some Panhandle communities before it sweeps through the Southeast and goes out to sea over the next few days.
Forecasters said it could bring 3 to 6 inches of rain to Georgia, the Carolinas and Virginia, triggering flash flooding in a corner of the country still recovering from Hurricane Florence.
"I know people are fatigued from Florence, but don't let this storm catch you with your guard down," North Carolina Gov. Roy Cooper said, adding, "A number of homes have rooftop tarps that could be damaged or blown away with this wind."
While Florence took five days between the time it turned into a hurricane and the moment it blew ashore in the Carolinas, Michael gave Florida what could amount to just two days' notice. It developed into a hurricane on Monday.
At the western end of the Florida Panhandle, in and around Pensacola, Escambia County Sheriff David Morgan bluntly warned people: "If you decide to stay in your home and a tree falls on your house or the storm surge catches you and you're now calling for help, there's no one that can respond to help you."
Michael wasn't quite done wreaking havoc in the Caribbean.
In Cuba, it dumped more than 10 inches (27 centimeters) of rain in places, flooding fields, damaging roads, knocking out power and destroying some homes in the western province of Pinar del Rio. Cuban authorities said they evacuated about 400 people from low-lying areas.
Disaster agencies in El Salvador, Honduras and Nicaragua reported 13 deaths as roofs collapsed and residents were carried away by swollen rivers.
In Florida, Scott declared a state of emergency for 35 counties, from the Panhandle to Tampa Bay, activated hundreds of Florida National Guard members and waived tolls to encourage evacuations. The governors of Alabama and Georgia also declared emergencies.
With just a month to go before Election Day, Florida voters in evacuation zones were given an extra day to register to vote, once offices reopen after the storm.
Scott also told Florida hospitals and nursing homes to do all they can to assure the safety of the elderly and infirm. After Hurricane Irma last year, 14 people died when a South Florida nursing home lost power and air conditioning.
"If you're responsible for a patient, you're responsible for the patient. Take care of them," he said.
In the small Panhandle city of Apalachicola, Mayor Van Johnson Sr. said the 2,300 residents were frantically preparing for what could be a blow unlike any seen there in decades. Many filled sandbags, boarded up homes and lined up to buy gas and groceries.
"We're looking at a significant storm with significant impact, possibly greater than I've seen in my 59 years of life," Johnson said of his city on Apalachicola Bay, where about 90 percent of Florida's oysters are harvested.
Farther inland, in the state capital, Tallahassee Mayor Andrew Gillum, Florida's Democratic nominee for governor, helped people fill sandbags.
"There's nothing between us and this storm but warm water, and I think that's what terrifies us about the potential impacts," Gillum said.