- Hurricane Irma started hitting the Leeward Islands, the chain of islands separating the Caribbean Sea from the Atlantic Ocean, early Wednesday.
- By Friday afternoon, the storm had caused severe damage in Anguilla, Antigua and Barbuda, St. Kitts and Nevis, Montserrat, St. Martin, St. Barthelemy, the Virgin Islands, and Puerto Rico.
- The monster Category 4 storm is spreading over Cuba and the central Bahamas, and is forecast to hit Florida on Sunday.
Hurricane Irma, one of the strongest Atlantic hurricanes ever recorded, started slamming the southeastern Caribbean islands early Wednesday with devastating winds, heavy rains, and catastrophic storm surges.
As of 5 p.m. ET Friday, the Category 4 storm'seye was 345 miles southeast of Miami with maximum sustained winds of 155 mph. The National Hurricane Center said the hurricane was cruising west at 12 mph.
The NHC reports that Irma is spreading over parts of Cuba and the central Bahamas. Its center is expected to turn northwest and wind up near the Florida Keys by Sunday morning, though the state could see extreme winds by Saturday morning.
"Irma is expected to make landfall in Florida as an extremely dangerous major hurricane, and will bring life-threatening wind impacts to much of the state regardless of the exact track of the center," Lixion Avila, a senior hurricane specialist at the NHC, wrote in a forecast on Friday.
What's next
The National Weather Service's latest forecast puts the entire state of Florida in the storm's crosshairs, with Irma most likely making landfall on Sunday morning. The storm is expected to travel up the peninsula on Sunday night and Monday, then head for Georgia and Alabama on Tuesday and Tennessee on Wednesday, though weather models still aren't sure what Irma's precise location or strength will be next week.
Hurricane warnings are in effect around much of the Florida coast — from Sebastian Inlet south around the Florida peninsula to Anna Maria Island. Warnings are also in place for the Florida Keys, Lake Okeechobee, Florida Bay, and parts of Cuba and the Bahamas.
A hurricane watch is in place along parts of Florida's east and west coasts, north of Sebastian Inlet and Anna Maria Island, as well as for parts of Cuba.
"Irma poses the most serious hurricane threat to northern Cuba and Florida since at least Hurricane Andrew" in 1992, Jeff Masters, a meteorologist, wrote on Weather Underground on Tuesday.
Life-threatening winds
While Hurricane Harvey brought devastating floods late last month, Irma's biggest threat is likely to be its strong winds.
Irma is now a Category 4 storm on the Saffir-Simpson scale, which measures a hurricane's strength based on its wind speeds. The scale goes up to 5, but if it had been extended to classify Irma's highest sustained wind speeds of 185 mph, the storm could have been considered Category 6 at one point, though that's not an official designation.
Part of what makes this storm so dangerous is its sheer size — hurricane-force winds extend up to 70 miles from Irma's center, and tropical-storm-force winds extend up to 185 miles, according to the NHC.
Florida's peninsula is only about 140 miles across at its widest, so Irma could engulf the entire state with its powerful winds.
Dangerous flooding
Irma's storm surge — the quick rise in water caused by a hurricane's strong winds — and wave height could also be devastating.
A storm-surge warning is currently in effect in the Florida Keys and around the bottom of the state's peninsula between Sebastian Inlet and Venice. The NHC expects a storm surge of 8 to 12 feet above ground in some of those areas if the hurricane hits during high tide.
The NHC predicts storm-surge and large breaking waves could raise water levels of 15 to 20 feet above normal in the southeastern and central Bahamas, and 5 to 10 feet on the northern coast of Cuba and in the northwestern Bahamas.
The NHC expects between 8 and 15 inches of rain in the Florida Keys and much of the state's peninsula, as well as parts of Georgia, with isolated areas getting up to 20. The southern Bahamas and northern Cuba could see 10 to 15 inches, with some areas getting up to 20 as well.
The rains could cause "life-threatening" flash flooding and mudslides, the NHC says.
Threats to the US mainland
The NHC is forecasting Irma will make landfall in Florida as a catastrophic hurricane this weekend, and forecasters advise residents to heed the advice of local officials and get ready if they are in the projected path of the storm.
The Florida Keys and the southern tip of the state are the most likely to see the worst effects of the storm before Irma starts to weaken slowly after making landfall.
Forecasters aren't positive yet how Irma will move up the East Coast, though the models are indicating the storm could hit Georgia, Alabama, Tennessee, and parts of South Carolina and Kentucky.
"Since Irma is a large hurricane, [forecast] users are reminded to not focus on the exact forecast track since tropical-storm and hurricane-force winds and life-threatening storm surge extend far from the center," Daniel Brown, a senior hurricane specialist at the NHC, wrote on Tuesday.
"Everyone in hurricane-prone areas should ensure that they have their hurricane plan in place."
SEE ALSO: Hurricane Irma is now a Category 5 storm and could make landfall in Florida
DON'T MISS: Full Irma coverage here
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