Latest Irma track shifts west with hurricane watch widened

National Hurricane Center

Hurricane Irma tightened her grip on South Florida Friday, becoming what everyone has long dreaded: a monster hurricane bearing down on a region with nearly 7 million people.

Reliable forecast models projecting the storm’s path predictably began to agree on a final, fateful track, with a direct hit along the south coast Sunday after crossing the middle Keys — although any wobble at this point could still change the storm’s course. The latest forecasts continue to nudge the storm west, but even at two days tracks have an 80 to 90-mile margin of error, National Hurricane Center forecaster Mike Brennan said.

Irma is heading west and should continue moving in that direction over the next 24 hours, forecasters said Friday, with hurricane conditions in the Keys and mainland starting Saturday night. Tropical storm-force winds should start in the morning. Forecasters are increasingly concerned about flooding, with high storm surge and heavy rain expected and likely to occur at high tide in vulnerable places like Miami Beach.

Irma was located just 380 miles southeast of Miami at 2 p.m. Warnings and watches encompass most of the state, from the the Volusia-Flagler county line on the east coast to just north of Tarpon Springs. A storm surge warning extends from Sebastian Inlet to Venice.

By late Saturday, the storm should begin making a critical turn to the north. But the turn will likely be too late to spare Florida from punishing hurricane winds that extend 70 miles from Irma’s center.

Overnight, the hurricane weakened slightly, with sustained winds at 155 mph Friday afternoon. Fluctuations in intensity are expected and Irma is still projected to hit as a dangerous Cat 4 storm, something not seen in South Florida since Andrew, a far smaller hurricane that slammed south Dade 25 years ago last month as a Cat 5.

Because Irma is moving south to north, the storm will likely make a “protracted slog” across South Florida, with hurricane-force winds lasting up to 12 hours, Brennan said. The hurricane should begin weakening quickly once it crosses land, but its sheer size mean damaging winds will still be far-reaching.

The storm’s eye also grew larger, to more than 45 miles across as it underwent an eyewall replacement. Such restructuring in fierce storms is common and can weaken the hurricane initially before recharging. In Irma’s case, the storm has rekindled with each replacement, and gotten wider. An eye expanding so much — the eye had been about half the size Thursday — usually signals a new eye forming that will tighten and shrink as the hurricane spins forward.

Because a hurricane’s most catastrophic winds blow near the eye, where the center tracks matters. Miami-Dade and the east coast remain on the storm’s dirty, stronger side.

“The best case would be to have it pass far enough way that the eyewall completely misses,” said University of Miami hurricane researcher Brian McNoldy. “It’s such a narrow kind of range. It doesn’t take much. A difference of 25 miles is kind of insignificant in terms of track forecast, but it is significant.”

There’s also a possibility Irma weakens the closer is passes Cuba Friday, forecasters said, but that remains to be seen.

Overnight, Irma continued rolling through the Caribbean after pounding islands in the French territories. The Turks and Caicos, where communications were knocked out, reported roofs ripped off, widespread blackouts and flooding. Dangerous storm surge and heavy rain will likely continue pounding the islands through Saturday, with heavy rain also forecast for Hispaniola.

The U.S. Virgin Islands lost its 911 call lines. The small island of Barbuda reported damage to 95 percent of the island, including its hospital and airport. At least 11 deaths so far have been blamed on the storm, with dozens more injured. The number of deaths is likely to climb.

Irma is moving between Cuba’s north coast and the southeastern Bahamas today, where storm surge could reach an astonishing 20 feet.

All of South Florida remains under a hurricane warning, with evacuation orders for parts of Miami-Dade and Broward counties, that include 680,000 people in Miami-Dade. All residents and visitors have been ordered out of the Keys. A watch has also been extended north along the east coast to Sebastian Inlet and on the west coast to Anna Maria Island, essentially putting the entire lower half of the state on alert.

On Friday, Gov. Rick Scott also ordered the evacuations of seven cities just south of Lake Okeechobee over concerns that the lake’s 1930’s era dike might fail. Evacuations also spread across 15 other counties, including parts of Palm Beach, Martin, St. Lucie, Collier and Pinellas counties.

The South Florida coast and Keys are also under a storm surge warning, with surge levels projected to reach between five and 10 feet on the east coast and six to 12 feet from Cape Sable to Captiva.

“It could be as high as your head, or twice that high,” Brennan said. “That’s life-threatening.”

Because Biscayne Bay is so shallow, wind can easily pick up and move water, he said.

“You’re going to have water blowing up Biscayne bay. The bay responds really fast. It’s shallow. So the bay’s going to respond very quickly to that wind,” he said.

And places in the Keys may get slammed by a double whammy of storm surge.

“The Keys could get storm surge from both sides,” Brennan said. “You can get almost two separate rounds.”

Florida’s west coast, particularly in the Naples area, could see significant storm surge as winds whip around from the west, pushing water from the Gulf’s shallow continental shelf ashore.

South Florida could also get heavy rain, with 10 to 15 inches across the Upper Keys — and up to 20 inches possible in some places — and up to 12 inches on the east coast, with 16 inches in some locations.

While Irma compares in intensity to Andrew, Brennan said the impacts from the storms will likely be different. Andrew approached the coast perpendicularly, plowing westward over South Dade after hitting Elliott Key, and chewing up Country Walk and other neighborhoods in its path. Irma is coming from the south, moving northward and pushing water expected to cause more surge across a wider swath, before plowing up the peninsula into Central Florida.

“Every storm is always different.” Brennan said. “The hazards are always different.”

Forecasters are also tracking a second hurricane, Jose, that became a Cat 4 storm with 150 mph winds Friday morning likely to near the northern Leeward Islands tonight. It’s not expected to hit the U.S. coast, but could be disastrous for islands still reeling from Irma.

It’s the first time on record two hurricanes with winds of 150 mph or higher have been recorded in the Atlantic, said Colorado State University hurricane researcher Phil Klotzbach, although not the first time the basin has produced two Cat 4 storms at once.

“There’s been years where we’ve had three,” said hurricane center spokesman Dennis Feltgen. “Unusual, but not a record.”

The Associated Press contributed to this report.

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