Conditions in the Florida Keys will become increasingly dangerous as Hurricane Irma closes in over the next day, National Hurricane Center forecasters said in their 2 p.m. update.
In their latest advisory, forecasters said Irma was located 145 miles southeast of Key West, with sustained winds of 125 mph, making it a Cat 3 storm. Irma’s fierce eye will keep moving over the north coast of Cuba today. Once it clears the island and moves over warm water in the Florida Straits, it could strengthen. Major hurricane winds should reach the Keys at daybreak Sunday, creating life-threatening and catastrophic conditions, they said.
The National Weather Office in Key West was more blunt: “This is as real as it gets,” the office posted, in all caps, on its latest bulletin. “Nowhere in the Florida Keys will be safe.”
Already ranked as one of the most powerful hurricanes on record, Irma weakened slightly Saturday when it stalled over Cuba, battering the north coast. But it’s expected to regain strength as it crosses the Florida Straits, headed for the Lower Keys.
"Immediate concern right now is anyone in the Florida Keys," hurricane specialist Mike Brennan said. "Your life may be at risk."
Early Saturday, tropical storm force winds had started lashing parts of the Florida chain of islands, pushing storm surge ashore. Water level was up more than three quarters of a foot in Key West after 10 a.m. and 1.1 feet near Vaca Key. The center of the storm is not expected to pass until Sunday morning, before heading to Florida’s Gulf Coast. Winds well in excess of 100 mph are expected but the real worry is storm surge, which could push the Atlantic into the streets of Key West, Marathon and other islands.
Along the Gulf Coast, forecasters warned flooding from storm surge could be catastrophic.
"This is a big hurricane," said Jamie Rhome, NHC storm surge team leader. "And big hurricanes push more water."
Rhome warned everyone in Southwest Florida to leave, saying Irma, a vastly bigger storm with hurricane winds extending 70 miles from its center, poses far more danger than Hurricane Charley, which hit Captiva in 2004 before pushing up Charlotte Harbor.
Where Irma ultimately makes landfall on the mainland remains uncertain because of the storm’s angle to the coast, National Hurricane Center forecasters said.
The storm’s center could near Tampa Bay, which has not been struck by a major hurricane since October 1921, when the population was about 10,000, said hurricane center spokesman Dennis Feltgen. About 4 million people now live in the low-lying area.
“Big difference,” he said. “They’re incredibly vulnerable.”
Irma begin crossing the Florida Straits early Sunday. The center of the track crosses close to Cudjoe Key, where Hurricane Georges hit in 1998 and delivered a 10 to 12-foot storm surge, cut off water and electricity to the chain of islands, and left the Lower Keys a ragged mess. Hurricane and storm surge advisories have been widened in Florida and up the U.S. east coast.
The Keys should brace for a “very life-threatening event,” Brennan said, with storm surge capable of reaching 10 feet above ground level. By 10 a.m. Saturday, winds at Molasses Reef off Key Largo had already reached 39 mph, he said.
Miami and the southeast coast have dodged a direct hit, but the east coast can still expect dangerous storm surge as strong winds push water inland and feeder bands drop heavy rain. Storm bands reaching Miami with squally rains and winds beginning just after 7 a.m. — signaling the storm’s astonishing reach. Storm surge pushed water levels 1.27 feet above normal with a gust nearing 50 mph. Miami International Airport recorded a 55 mph gust.
A tornado watch was issued just after noon until midnight, with the National Weather Service warning that Irma’s approaching bands has raised the risk. Wind gusts could also reach 70 mph, they said. The watch stretches across the state, from Lake Okeechobee south to 40 miles east of Marathon.
Long periods of thunderstorms should begin tonight as conditions worsen, said Mark DeMaria, the acting deputy director of the National Hurricane Center.
"This is a major storm surge threat, a major wind threat for a large portion of Southwest Florida," he said.
Irma remains massive, with tropical storm force winds extending 195 miles — making it wider than the state. Its eye shrank dramatically overnight, from more than 45 miles wide to just over 11. The storm is expected to batter Florida for at least two days, Brennan said. The latest forecast track also crosses dangerously close to Captiva and Sanibel in an eerie repeat of Charley. But hurricane wobbles are notorious. Forecast tracks can still be off by about 90 miles at two days, Brennan said.
Saturday morning, Irma unexpectetdly plowed ashore Cuba’s north coast, near Caibarién, a village nicknamed The White Town for beaches that once supported a thriving resort. In 2009, the population was about 38,000.
Along Florida’s Gulf Coast, flooding is expected to be widespread, with dangerous and potentially catastrophic storm surge rolling up and down the Florida coast.
Above-ground water levels could reach up to 10 feet along the east coast from Cape Sable to Boca Raton, forecasters said. On the Gulf coast, where the flat continental shelf worsens the threat, the surge could reach 15 feet from the cape to Captiva. Flood-prone Tampa could see three to five feet.
Heavy rain could worsen flooding. Up to 15 inches are possible in the Keys, with up to 20 inches in some places. The Florida mainland is expected to get between eight and 15 inches.
The record-breaking hurricane — Irma accumulated more wind energy in 48 hours than any hurricane ever recorded — has been menacing South Florida for days. Track forecasts earlier pointed it to the urban east coast, home to more than 6 million, triggering frantic preparations. Evacuations were ordered that affected about 680,000 people in Miami-Dade alone. Gas pumps ran dry. Store shelves quickly emptied.
As forecasts began shifting west, taking the storm up the center of the state, evacuations increased to eventually cover nearly 20 counties.
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