Hurricane Irma is so record-breakingly strong it is impossible to hype and holds about twice the energy of all the bombs used in World War II, experts have said.
Louis Uccellini, director of the National Weather Service, said he was concerned about Florida up the east coast to North Carolina, starting with the Florida Keys.
He warned “all the hazards associated with this storm” are going to be dangerous.
Hurricane expert Kerry Emanuel of MIT calculated Irma holds about 7 trillion watts – twice the energy of all the bombs used in World War II.
So far, the storm has killed at least eight people and left 23 injured on French island territories, France’s interior minister has said.
“This is not, by far, a definitive number… we have not explored all the parts of the island,” Guadeloupe prefect Eric Maire said, adding the death toll was likely to rise in the next few hours.
View of the aftermath of Hurricane Irma on Saint Martin
Netherlands Ministry of Defence via REUTERS
An aerial photograph taken and released by the Dutch department of Defense shows the damage of Hurricane Irma in Philipsburg, Sint Maarten, the Dutch section of the Caribbean Island
Gerben Van Es/AFP
Flooded houses in Gustavia on the island of Saint-Barthelemy
The damage on the island of Saint-Martin, a day after Hurricane Irma hit
People pick up debris in Fajardo as Hurricane Irma howled past Puerto Rico after thrashing several smaller Caribbean islands
A man carrying an umbrella is battered by the wind in Fajardo, Puerto Rico
A lone police car on patrol during the passing of Hurricane Irma in Fajardo, Puerto Rico
Jose Jimenez/Getty Images
A flooded street on the island of Saint Martin
A tree collapsed on a house in Saint Martin
A hotel in Saint Martin is gutted by floodwater during the hurricane
Cars submerged in Saint Martin
Debris floats amongst the floodwater in Saint Martin
Household items float down the street in Gustavia, Saint-Barthélemy
The coast of Saint Martin is flooded as the hurricane hits the island
A whole street underwater in Saint Martin
A car crashes into the tree amongst the chaos in Saint Martin
A building on the Saint Martin seafront, destroyed by the hurricane
A mobile home overturned at Princess Juliana International Airport in Saint Martin
Palm trees bend in the wind in San Juan, Puerto Rico as Hurricane Irma slammed across islands in the northern Caribbean
A woman runs in the rain as Hurricane Irma slammed into San Juan, Puerto Rico
A picture taken on September 5, 2017 shows a view of the Baie Nettle beach in Marigot, with the wind blowing ahead of the arrival of Hurricane Irma
A man rides past a boarded up house as part of preparations ahead of the arrival of Hurricane Irma on September 5, 2017, in the French overseas island of Guadeloupe
Employees of the Mercure Hotel fill sand bags on the Baie Nettle beach in Marigot, as part of the preparations for the arrival of Hurricane Irma
People in line at Costco, as they find out the store has ran out of water on September 5, 2017 in North Miami
Michele Eve Sandberg/AFP
Night view of the city of Cap-Haitien, in the north of Haiti, 240 km from Port-au-Prince, on September 5, 2017
Bonjour Food Market in Miami prepares for Hurricane Irma
Michele Eve Sandberg/AFP
A mobile network tower snapped in two by the hurricane on the island of Barbuda
Hurricane Irma had previously been described as a “potentially catastrophic” storm placed in Category 5, the highest US classification for hurricanes.
The storm blacked out much of Puerto Rico as it raked the US territory with heavy wind and rain while staying just out to sea, as it headed toward the Dominican Republic and Haiti.
To the east, authorities struggled to get aid to small Caribbean islands devastated by the storm’s record 185mph (298kph) winds, while people in Florida rushed to get ready for a possible direct hit on the Miami area.
Nearly every building on Barbuda was damaged when the hurricane’s core crossed almost directly over the island early Wednesday and about 60 percent of its roughly 1,400 residents were left homeless, Antigua and Barbuda Prime Minister Gaston Browne said.
President Donald Trump approved an emergency declaration for the US Virgin Islands and Puerto Rico, allowing the Federal Emergency Management Agency and other agencies to remove debris and give other services that will largely be paid for by the US government.