As South Florida fell under hurricane warnings, gas shortages and gridlock plagued thousands of people fleeing North ahead of Irma.
More than a half-million people have been ordered to evacuate to escape the Category 5 hurricane tracking toward the state, and that volume turned normally simple trips into tests of will.
"I encourage EVERYONE in the path of #HurricaneIrma to heed the advice and orders of local & state officials!" President Donald J. Trump announced.
"We will confront ANY challenge, no matter how strong the winds or high the water."
Late Thursday, the National Hurricane Center issued the first hurricane warnings for the Keys and parts of South Florida, including some of the Miami metropolitan area of 6 million people and Lake Okeechobee. It added a storm surge warning and extended watch areas wrapping around the tip of the peninsula.
"Don't even dial 911 [emergency services] because nobody is going to answer" Florida authorities said.
People along the Atlantic coast anxiously watched the behemoth while Irma battered the northern Caribbean, killing at least 14 people and leaving thousands homeless after destroying buildings and uprooting trees.
The casualties in the Caribbean are expected to rise into the dozens, as thousands, if not tens of thousands of houses and other buildings have been completed decimated. Some islands have lost over 90 percent of their houses, buildings and other infrastructure.
Being described as a 'nuclear hurricane' by some witnesses on the ground, their comments are not far off as the landscape left behind by Irma does remind one of old footage of nuclear bombs going off and taking down thousands of buildings in the process.
Some of the affected islands, such as St. Martin, are classified as Outermost Regions of the European Union.
French, British and Dutch military authorities rushed aid to a devastated string of Caribbean islands. Warships and airplanes were sent with food, water and troops in order to conduct aid and relief operations. The damages are already exceeding 200 million euros, a figure which is also expected to rise significantly.
At least 31,000 people fled the Florida Keys, which could begin seeing wind and rain from Irma as early as Friday night, Gov. Rick Scott said. He noted the size of the powerful storm, and told residents not to become complacent.
"It is wider than our entire state and could cause major and life-threatening impacts from coast to coast. Regardless of which coast you live on, be prepared to evacuate," Scott said. He ordered all public schools, colleges and universities to close Friday through Monday.
With winds that peaked at 185 mph (300 km/h), Irma has been the most powerful hurricane ever recorded in the Atlantic.
NASA secured Kennedy Space Center and SpaceX launched an unmanned rocket for an experimental flight. Kennedy closed its doors to all nonessential staff and a crew of about 120 people will ride out the storm on site.
Most of the critical buildings at Kennedy are designed to withstand gusts of up to 135 mph (220 kph). Irma's wind could exceed that if it reaches Cape Canaveral.
Georgia Gov. Nathan Deal ordered evacuations for all areas east of Interstate 95, including the city of Savannah, and authorized about 5,000 National Guard members to help with response and recovery. Georgia was last struck by a hurricane of force Category 3 or higher in 1898.
Irma's eventual path and Florida's fate depends on when and how sharp the powerful hurricane takes a right turn, National Weather Service Director Louis Uccellini said.
"It has become more likely that Irma will make landfall in southern Florida as a dangerous major hurricane," the Hurricane Center said in a forecast discussion Thursday afternoon.
The last Category 5 storm to hit Florida was Andrew in 1992. Its winds topped 165 mph (265 kph), killing 65 people and inflicting $26 billion in damage [about $50 billion in current dollars.] It was at the time the most expensive natural disaster in U.S. history.
U.S. Air Force Reserve weather officer Major Jeremy DeHart flew through the eye of Irma at 10,000 feet Wednesday and through Hurricane Harvey just before it hit Texas last month.
He said Irma's intensity set it apart from other storms.
"Spectacular is the word that keeps coming to mind. Pictures don't do it justice. Satellite images can't do it justice," DeHart said.
While Hurricane Harvey infictled significant amounts of damage in Texas, the major difficulties with it stemmed from all the subsequent flooding that occurred; its wind speeds however were nothing to compared to Irma's 300 km/h gushes.
"The effect of Irma on the state of Florida is going to be much greater than Andrew's effect," said Weather Channel senior hurricane specialist Bryan Norcross, who was a local television meteorologist hailed as a hero during Andrew. "We're dealing with an entirely different level of phenomenon. There is no storm to compare with this. Unless you go way back to 1926."