SAN JUAN, Puerto Rico (AP) — Hurricane Irma grew into a dangerous Category 5 storm, the most powerful seen in the Atlantic in over a decade, and roared toward islands in the northeast Caribbean Tuesday on a path that could eventually take it to the United States.
The U.S. National Hurricane Center said Irma was a "potentially catastrophic" storm with maximum sustained winds of 180 mph (285 kph) as it bore down on the twin-island nation of Antigua and Barbuda. It was centered about 225 miles (365 kilometers) east of Antigua in the late morning and moving west at 14 mph.
The center said there was a growing possibility that the storm's effects could be felt in Florida later this week and over the weekend, though it was still too early to be sure of its future track: "Everyone in hurricane-prone areas should ensure that they have their hurricane plan in place."
Irma's center was expected to move over portions of the northern Leeward Islands late today and early Wednesday, the hurricane center said. The eye was then expected to pass about 50 miles (80 kilometers) from Puerto Rico late Wednesday.
Irma is the strongest Atlantic hurricane since Rita in 2005, officials said.
"Puerto Rico has not seen a hurricane of this magnitude in almost 100 years," Carlos Anselmi, a National Weather Service meteorologist in San Juan, told The Associated Press.
Authorities warned that the storm could dump up to 12 inches of rain, cause landslides and flash floods and generate waves of up to 23 feet. Government officials began evacuations and urged people to finalize all preparations as shelves emptied out across islands including Puerto Rico.
"The decisions that we make in the next couple of hours can make the difference between life and death," Puerto Rico Gov. Ricardo Rossello said. "This is an extremely dangerous storm."
Hurricane warnings were issued for 12 Caribbean island groups including Antigua, where buzzing chainsaws and pounding hammers could be heard Tuesday. Crews delivered water to neighboring Barbuda, one of the islands closest to the hurricane's path.
Both Puerto Rico and the U.S. Virgin Islands expected 4 inches to 10 inches of rain and winds of 40-50 mph with gusts of up to 75 mph.
In Florida, residents took advantage of the Labor Day holiday to empty many store shelves of drinking water and other supplies in advance of the storm. Gov. Rick Scott declared a state of emergency for the state's 67 counties to give local governments "ample time, resources and flexibility" to prepare. A new tropical storm also formed in the Atlantic on Tuesday, to the east of Irma. The hurricane center said Tropical Storm Jose was about 1,505 miles east of the Lesser Antilles with maximum sustained winds of 40 mph. It was expected to become a hurricane by Friday.