As Hurricane Irma’s eye wall began thrashing the Florida Keys as dawn broke on Sunday, South Florida was waking up to an unwelcoming reality: a high risk of dangerous storm surge.
While escaping the brunt of Hurricane Irma, parts of the Miami area could experience a storm surge of 5 to 10 feet above sea level. Some areas were already reporting significant surges and flooding.
Hurricane Specialist Mike Brennan said he wouldn't be surprised if the storm surge from Homestead, through Cutler Bay and up along the coast toward Miami pushed inland “a couple of miles.”
Key West and islands up and down the chain could see even worse surge as Irma pushes rising water from the east, turns and hits the west side of the islands, Brennan said. That’s because waves of equal height could ride on top of the surge. Key West could see “catastrophic” damage and “the storm surge on top of that can literally wipe structures entirely away,” he said. Indeed, on-the-ground reports were already coming in Sunday morning.
The worst surge will occur near and to the right eye of the storm, the Key West office of the National Weather Service said early Sunday. Storm surge is likely already occurring, they said, and will peak around midday before receding early Monday morning.
Larry Kahn, editor of the Keynoter and an editor for FlKeysNews.com, reported from a shelter set up at Marathon High School on Sombrero Road that everything outside was submerged by storm surge and rain. “Everything is underwater. I mean everything,” Kahn said.
Flooding from storm surge could be even worse in South Florida because it coincides with some of the highest tides of the year. September’s tides are second only to October’s king tides, exposing low-lying areas — including Miami, Miami Beach, Fort Lauderdale and the Keys — to an even more dangerous surge risk.
Brennan said water was already dangerously stacking up in Biscayne Bay. It’s a “very, very dangerous few hours for those in South Florida,” he said. Late morning Sunday, Biscayne Bay was already seeing a four-foot rise.
Along Florida's West Coast, a 10 to 15 foot surge is projected. “If you're in an evacuation zone, you do not want to be there when the surge comes. You can lose your life, it's as simple as that,” Brennan said.
Together with rainfall from Irma over the next 12 hours, the South Florida region is likely facing flooded, soggy streets. Some streets in downtown Miami and Miami Beach already looked like shallow streams in the wee hours Sunday.
The National Weather Service in Miami has issued a flood warning for most Florida’s southern peninsula. The warning, in effect until 4:45 p.m. Sunday, is for “urban areas and small streams” in Miami-Dade, Broward and Collier counties, and for the southern portion of Hendry County.
In South Florida, 8-15 inches of rain is expected in most places, and more than 20 inches possible in some locations. Expected to flood are Miami, Hialeah, Fort Lauderdale, Homestead, Pembroke Pines, Hollywood and Naples.
Miami Herald staff writers Charles Rabin and Patricia Mazzei. This report will be updated. Follow @ndahlberg on Twitter.