Hurricane watch issued for South Florida

South Florida came under hurricane and storm surge watches Thursday morning as powerful Hurricane Irma steamed toward the peninsula.

Tropical storm force winds could begin battering the Keys and South Florida early Saturday, National Hurricane Center forecasters said in their latest advisory. The fierce center of the Cat 5 storm is also increasingly likely to plow across the state’s crowded east coast, and it’s more than 6 million residents, in three to four days.

The hurricane and storm surge watches cover much of the South Florida coast, from Jupiter Inlet south and up the west coast to Bonita Beach, including the Keys. Water levels could reach from between five and 10 feet above normal levels in the storm surge watch area, forecasters said.

Because Irma is such a large area, the storm surge could be widespread, said senior hurricane specialist Mike Brennan, with waters moving further inland along the Gulf.

A high pressure ridge is steering the storm, but the ridge should weaken when it collides with a low pressure trough moving across the U.S., letting Irma turn north. Exactly when and where that happens remains less certain, leaving the target of the hurricane’s ferocious core unclear. But Thursday’s early computer runs continue to turn Irma sooner, rather than later.

Overnight, sustained winds dropped slightly to 175 mph, with Irma’s eye clouding over. The storm became a little less organized, forecasters said, but only slightly so. Fluctuations in intensity are expected, but it will almost certainly remain a dangerous Cat 4 or 5 storm in the coming days, forecasters said.

At 11 a.m., Irma was located about 75 miles east of the Dominican Republic’s east coast, heading west-northwest at 18 mph. Hurricane winds extend 50 miles from the storm’s center, with tropical storm force winds reaching nearly 200 miles.

South Florida continued making frantic preparations early Thursday, with highways growing clogged, long lines at gas pumps — and some already drained — and supplies flying off shelves. To speed up refilling gas stations, Gov. Rick Scott ordered state police to escort fuel trucks through traffic.

“We know fuel is important and absolutely devoting every state resource to addressing this,” Scott said. “While we are making progress, you will see lines and outages.”

Evacuation orders have been issued for barrier islands, the coast and low-lying areas in Miami-Dade and Broward counties. All residents and visitors have been ordered out of the Keys. Miami-Dade has opened eight shelters, with Metro buses ferrying passengers until 10 p.m.

In the coming hours, Irma is expected to begin pounding the southeastern Bahamas and Turks and Caicos, forecasters said. It should near the Central Bahamas Friday.

The low-lying islands will likely see high storm surge, reaching as much as 20 feet above normal tide levels through Thursday night and possibly early Friday, forecasters said. Rainfall could reach eight to 12 inches. On the island of South Caicos, officials cut off power early this morning in advance of the storm.

Overnight, Irma plowed across the western Caribbean, killing at least 10 people and injuring 23.

French Interior Minister Gerard Collomb told the Associated Press the death toll in St. Martin and St. Barthelemy could be higher because rescue teams have not finished inspecting the islands.

“The reconnaissance will really start at daybreak,” Collomb said.

Barbuda suffered damage to 95 percent of the island, Prime Minister Gaston Browne said.

“I felt like crying,” he said after seeing the devastation, “but crying will not help.”

Puerto Rico narrowly dodged Irma’s strongest winds but still suffered widespread blackouts, with about 70 percent of the island without power Thursday morning. Three deaths were blamed on the storm.

Over the next two days, Irma is expected to keep moving in the same direction around the southwestern edge of the ridge and and begin to slow, according to the latest track models. The trough — moving from the Midwest and tracked by meteorologists around the country with weather balloons launched every six hours — should begin to erode the ridge, letting Irma slide north.

But the timing and speed of the turn remains less certain, forecasters said, leaving Irma’s precise path unclear and a margin of error of about 120 miles at three days and 175 miles at four days.

Three models show a later turn, once the storm enters the Gulf of Mexico, near Florida’s west coast, while the reliable European models have Irma turning sooner and heading over southeast Florida. U.S. models turn Irma even sooner and rumbling up the east coast.

Based on trends, and a widely regarded Florida State University model, forecasters believe Irma will likely head over southeast Florida in the next 72 to 96 hours.

Forecasters are also tracking a second hurricane, Jose, which is expected to become a major hurricane Friday. Early this morning, the hurricane was located about 800 miles east of the Lesser Antilles with sustained winds of 90 mph. The compact storm, with hurricane winds extending just 15 miles from its center, is expected to near the islands Saturday.

Staff writer Jacqueline Charles and the Associated Press contributed to this story.