Hurricane Irma might deal a direct blow to Miami, new models suggest, but there’s still plenty of time for that to change.
Computer runs that earlier leaned to the east shifted back to the west Thursday evening, putting Miami at the center of the Category 5 hurricane. That could change as models wobble, and regardless, damaging winds could spread across the state as Irma ambles over land. Hurricane-force winds extend 140 miles across and tropical storm force winds reach nearly 400 miles.
Earlier in the day, all of South Florida came under hurricane and storm surge watches, from Jupiter Inlet south and up the west coast to Bonita Beach, from the Keys to Lake Okeechobee. That warning could be expanded north later Thursday night. Tropical storm force winds are expected to begin battering the Keys and South Florida Saturday afternoon, National Hurricane Center forecasters said at 5 p.m. Thursday.
In a worst-case scenario, Florida surge waters could reach life-threatening levels of between five and 10 feet above ground, forecasters said.
The storm surge might also be widespread, fueled by Irma’s sheer size, senior hurricane specialist Mike Brennan said. Along the Gulf’s flat coastal shelf, waters could rise far inland. In Key West, forecasters warned that debris might leave roads and bridges impassable.
“That’s what’s driving a lot of the evacuations,” Brennan said.
The surge watch area includes wide swaths of Miami-Dade County, where Mayor Carlos Gimenez expanded evacuation orders Thursday, including downtown Miami, parts of Coral Gables, Kendall, North Miami, Florida City and Homestead. Further north, it hews closer to the coast.
In Key West, ocean waters could rise as high as eight feet, forecasters warned, accompanied by battering waves. Winds that are expected to pick up Saturday afternoon may cause “structural damage to sturdy buildings, some with complete roof and wall failures.”
By 8 p.m. Thursday, Irma was “pummeling” the Turks and Caicos, according to the National Hurricane Center. It was expected to reach the Bahamas later in the coming hours, forecasters said. Parts of Cuba’s north coast are also expected to get slammed with hurricane force winds before Irma arrives in Florida.
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, measuring 25 to 30 miles wide, unclear.
Sustained winds remain at 175 mph, as of 8 p.m. The storm became a little less organized overnight, 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, they said.
At 8 p.m. Thursday, Irma was located about 55 miles west southwest of Grand Turk Island. Irma’s center is expected to move between Cuba’s north coast and the Bahamas over the next day or two. In advance of the storm Thursday afternoon, the Turks and Caicos government ordered all residents to stay indoors and put the island on lock down. The Cuban government also issued hurricane warnings.
South Florida continued making frantic preparations Thursday, with highways growing clogged, long lines at gas stations — and many 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 were expanded Thursday from the beaches and coastal areas inland, to cover large parts of Miami-Dade County — where about 650,000 people live — including Homestead, Florida City, parts of Coral Gables, Miami Shores and North Miami Beach. The county now has eight shelters open. Broward County has also ordered residents to leave the coast and low-lying areas. All residents and visitors have been ordered out of the Keys.
The low-lying islands of the Bahamas and Turks and Caicos 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 Thursday morning in advance of the storm.
Overnight, Irma plowed across the Western Caribbean, killing at least 10 people, including a toddler on Barbuda, and injuring at least 50.
French Interior Minister Gerard Collomb told The Associated Press the death toll in St. Martin and St. Bart’s 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. Its lone hospital was damaged and the roof blown off the airport. The island came under a second hurricane watch Thursday, with Hurricane Jose risking a second hit after becoming a damaging Cat 3 storm.
“I felt like crying,” Browne 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.
After analyzing the latest track models, forecasters adjusted the track slightly south and to the west in their latest advisory. Over the next two to three days, Irma is expected to keep moving to the west-northwest around the southwestern edge of the ridge and and begin to slow. 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 remain 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. Wobbles are expected, which is why forecasters say more attention should be paid to the hurricane’s cone, and not a single track.
Forecasters are also tracking a second hurricane, Jose, which is expected to become a major hurricane Friday. Early Thursday 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.
Miami Herald staff writer Jacqueline Charles and The Associated Press contributed to this report.
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