Irma is the kind of storm where you get thousands of lives lost. This is not going to be the big slow-motion flood like Harvey - this is a real, honest-to-God hurricane.

- Chuck Watson, disaster modeler with Enki Research



Hurricane Irma, the most powerful Atlantic storm on record according to the NHC, raced across northern Caribbean islands on Wednesday with a "catastrophic mix of fierce winds, surf and rain", ahead of what appears a virtually guaranteed Florida landfall at the weekend. While Irma precise trajectory remained uncertain, the latest NHC forecast sees the cone coming right on top fo the panhandle.

.@NHC_Atlantic cone w/ #Irma & how its changed over time. Trend back to the right and a wide cone still relaying uncertainty on future track pic.twitter.com/Mr1a6CHDjx — Jim Cantore (@JimCantore) September 6, 2017

The eye of Irma, a Category 5 storm packing winds of 185 miles per hour (295 km per hour), moved away from the island of Barbuda and toward the island of St. Martin, east of Puerto Rico, early on Wednesday, the U.S. National Hurricane Center (NHC) in Miami reported. It could hit Florida on Saturday. It is expected to bring strong storm surges and up to 20 inches of rain in some places.

“We are hunkered down and it is very windy ... the wind is a major threat,” said Garfield Burford, the director of news at ABS TV and Radio on the island of Antigua, south of Barbuda. “So far, some roofs have been blown off” he added according to Reuters. Most people who were on Antigua and Barbuda were without power and about 1,000 people were spending the night in shelters in Antigua, according to Burford. “It’s very scary ... most of the islands are dark so it’s a very, very frightening,” he said.

The eye of the storm passed over St. Martin and its northern wall was pounding Anguilla, the U.S. National Hurricane Center said in an advisory around 8 a.m. New York time. It’s on a path that should pass near or just north of Puerto Rico later Wednesday, it said.

The French government has said that the four "most solid" buildings on the Caribbean island of Saint Martin have been destroyed by Irma as the Hurricane wreaked catastrophic damage in the region,

[IRMA] Saint Martin dans le mur de l'oeil subit les effets de l'ouragan IRMA #iram #ouragan #SaintMartin (Source : Rinsy Xieng) pic.twitter.com/e2j7e9KtOu — RCI Guadeloupe (@RCI_GP) September 6, 2017

Serious flooding and building damage has affected a number of islands, French interior minister Gerard Collomb said. "We know that the four most solid buildings on the island have been destroyed which means that more rustic structures have probably been completely or partially destroyed," he told reporters. The French government has said there are electrical blackouts and widespread flooding on the islands of St Barthélemy and St Martin.

Public relations professional Alex Woolfall said on Twitter he was hiding underneath a concrete stairwell as the storm neared St. Maarten.

“Still thunderous sonic boom noises outside and boiling in stairwell. Can feel scream of things being hurled against building,” he said. “Okay I am now pretty terrified so can every non-believer, atheist & heretic please pray for me.”

The amount of damage and the number of casualties were not known early on Wednesday. A 75-year-old man died while preparing for the storm in Puerto Rico’s central mountains, police said. Several other Leeward Islands, including Anguilla, Montserrat, St. Kitts and Nevis, as well as the U.S. and British Virgin Islands, Puerto Rico and the Dominican Republic were under a hurricane warning.

Anguilla’s Disaster Management Department said the island was experiencing extremely heavy winds and rain, the Associated Press reported on Wednesday. In Barbuda, phone lines went down and howling winds sent debris flying as people huddled in their homes or government shelters.

“Preparations to protect life and property should be rushed to completion,” the Hurricane Center said, warning that Irma “will bring life-threatening wind, storm surge and rainfall hazards” to those islands. Along the beachfront of Puerto Rico’s capital, San Juan, work crews scrambled to cover windows with plywood and corrugated metal shutters along Avenida Ashford, a stretch of restaurants, hotels and six-story apartments.

“I am worried because this is the biggest storm we have seen here,” said Jonathan Negron, 41, as he supervised workers boarding up his souvenir shop.

The NHC said Irma ranked as one of the five most powerful Atlantic hurricanes during the past 80 years and the strongest Atlantic basin storm ever outside the Caribbean Sea and Gulf of Mexico.

As the storm approached Puerto Rico, Governor Ricardo Rossello urged the 3.4 million residents of the U.S. territory to seek refuge in one of 460 hurricane shelters in advance of the storm and later ordered police and National Guard troops to begin evacuations of flood-prone areas in the north and east of the island.

“This is something without precedent,” Rossello told a news conference.

On Tuesday evening, President Trump approved emergency declarations for Florida, Puerto Rico and the U.S. Virgin Islands, mobilizing federal disaster relief efforts, the White House said.

Meanwhile, as the Hurricane approaches Florida, local authorities called for a mandatory evacuation of visitors in the Florida Keys to start at sunrise on Wednesday, and public schools throughout South Florida were ordered closed, some as early as Wednesday. Residents of low-lying areas in densely populated Miami-Dade County were urged to move to higher ground by Wednesday as a precaution against coastal storm surges, three days before Irma was expected to make landfall in Florida. It is likely that an evacuation for Miami will be called later today.

According to the latest meteorological forecasts, there is now a 50% chance for major hurricane force winds from Irma on Sunday-Monday in Miami.

Adding to concerns, the City of Miami warned resident to watch out for construction cranes, built to withstand 145 mph winds. Some advice from the city:

Do no stay in a building next to a crane

Comply with evacuation orders (if and when the city issues them)

If you live in a high-rise building and do not evacuate, take shelter in an enclosed concrete stairwell

City of Miami warns to watch out for construction cranes, built to withstand 145 mph winds. #Irma’s are 185 mph https://t.co/MkUCRMuMah pic.twitter.com/4Ko3fRcISv — CNN (@CNN) September 6, 2017

At the same time, residents of Texas and Louisiana were still recovering from Harvey, which struck Texas as a Category 4 hurricane on Aug. 25. It dumped several feet of rain, destroying thousands of homes and businesses, and displaced more than 1 million people.

As reported yesterday, should Irma hit Miami with the same force as a Category 4 storm that struck in 1926, insured losses would reach $125 billion to $130 billion, according to a Barclays analysis. Uninsured losses would be on top of that. Across the Caribbean the cost of damage could easily reach $8 billion to $10 billion, Watson said.

Only three Category 5 hurricanes have hit the contiguous 48 U.S. states, according to Weather Underground: The Labor Day Hurricane of 1935 that devastated the Florida Keys, Hurricane Camille in 1969 and Hurricane Andrew that cut across Florida in 1992.

Finally, following close on the heels of Irma is Tropical Storm Jose, which is expected to become a full blown Hurricane on Wednesday night, while Tropical Storm Katia has developed in the Gulf of Mexico...