Irma weakened slightly Thursday from its peak, record-setting winds of 185 mph (300 kph) but was expected to strengthen again.
WHAT'S AHEAD FOR IRMA?
Irma appears increasingly likely to rip into heavily populated South Florida early Sunday. Gov. Rick Scott has declared an emergency and mandatory evacuation orders are in place for parts of the Miami metro area and the Florida Keys.
Irma's top sustained winds weakened by about 10 mph (16 kph) on Thursday because of dry air and interaction with land on the island of Hispaniola. However, meteorologist Jeff Masters with Weather Underground, Irma could strengthen again to 185 mph" (298 kph) or higher as it heads to warmer deeper water.
Forecasters said Irma could rake the entire Atlantic coast of Florida and rage on into Georgia and South Carolina. Georgia's governor has ordered a mandatory evacuation starting Saturday from the state's Atlantic coast.
WHAT HAS IRMA DONE SO FAR?
French, British and Dutch rescuers struggled to rush aid to a string of Caribbean islands Thursday after Hurricane Irma left at least six dead and thousands homeless. Warships and military planes were dispatched with food, water and troops after the fearsome Category 5 storm smashed homes, schools and roads, laying waste to some of the world's most beautiful and exclusive tourist destinations.
Nearly every building on the island of Barbuda was damaged when the eye of the storm passed early Wednesday. That left about 60 percent of the island's roughly 1,400 people homeless, Antigua and Barbuda Prime Minister Gaston Browne told The Associated Press.
About a million people were without power in Puerto Rico after Irma sideswiped the island.
EVACUATION TRAFFIC JAMS
After parts of southern Florida were placed under an evacuation order, some drivers faced traffic jams and fuel shortages as they tried to head north to safety. 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.
The Republican governor acknowledged that traffic jams and gas shortages were "frustrating," and said federal authorities and other states were helping to move more fuel into the state. He urged gas stations to stay open as long as possible.
ONE FLIGHT INTO THE STORM
A daring Delta Air Lines crew braved Hurricane Irma's wind and rain to fly in and out of Puerto Rico to pick up travelers.
The flight-tracking website FlightRadar24 shared a radar image showing the plane heading into San Juan from New York just before noon Wednesday as the swirling storm was set to engulf the island. The plane took off less than an hour later with a new group of passengers for the return trip to New York. Radar images showed it navigating a narrow path between Irma's outer bands to escape the storm.
OTHER FLIGHTS BEING CANCELED
Airlines plan to cancel Florida flights that are in Hurricane Irma's path.
American Airlines says it will begin shutting down operations in Miami, Fort Lauderdale, Fort Myers, Sarasota and West Palm Beach by Friday afternoon and cancel flights through the weekend. JetBlue Airways said Wednesday afternoon that it had canceled about 130 flights.
American, JetBlue, United and Delta offered waivers letting customers change travel plans to Florida and the Caribbean without the usual charges for changing a ticket.
One of Florida's biggest home insurers could take a big hit if predictions about Hurricane Irma prove true.
The state-run Citizens Property Insurance Corp. is strong enough to absorb the blow from the monster storm, industry experts say, but all the new claims could punch a hole in its finances, possibly leading to higher premiums in future years.
FLOOD INSURANCE HAS DROPPED
An Associated Press analysis shows a steep drop in flood insurance across Florida, including the areas most endangered by what could be a devastating storm surge as Hurricane Irma approaches.
In just five years, the state's total number of federal flood insurance policies has fallen by 15 percent, according to Federal Emergency Management Agency data. Florida's property owners still buy far more federal flood insurance than any other state, but most residents in hazard zones are badly exposed.
TEST FOR FLORIDA'S BUILDING CODES
A catastrophic Hurricane Andrew revealed how lax building codes had become in the country's most storm-prone state. Florida responded by requiring sturdier construction . Now, experts say a monstrously strong Hurricane Irma could become the most serious test of Florida's storm-worthiness since the 1992 disaster.
RUSH LIMBAUGH'S REMARK
Rush Limbaugh created a storm of his own by suggesting that the "panic" caused by Hurricane Irma benefits retailers, the media and politicians seeking action on climate change.
The conservative radio personality's swerve into meteorology had Al Roker, the "Today" show weatherman, saying Wednesday that Limbaugh was putting people's lives at risk.
Limbaugh's lengthy soliloquy on his radio show the day before was apparently set off by seeing a rush on supplies of bottled water in South Florida, where he lives.
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