Remnants of Irma pound Charleston with tropical force winds, spawning squalls and stinging rain

September 11, 2017

Slowed by its march through Florida, Irma pounded Charleston with tropical storm force winds Monday morning, spawning squalls with stinging rain and driving a potentially record-breaking surge toward low-lying areas.

High tide in Charleston is 12:23 p.m., and forecasters expect water to rise quickly as that time nears. It will be a dramatic shift: Low tide this morning was nearly 3 feet less than normal; by noon, water levels could rise 4 to 6 feet above a typical high tide.

That would trigger flooding akin to what the area saw last year during Hurricane Matthew. Matthew generated a 10.23-foot tide – an extra 3.5-foot layer of water and the third-highest tide on record here. Hurricane Hugo’s roughly 6-foot surge generated a 12.5-foot tide.

Despite Irma’s falling strength, the storm’s massive bands still stretched 415 miles from its center, the National Hurricane Center said. And its degraded winds still generated powerful gusts: more than 50 mph at the north end of Folly Beach at 8:30 a.m., 43 mph gusts in Walterboro and 30 mph gusts at the Charleston International Airport throughout the morning.

Irma’s bands also brought heavy rain, and forecasters expect as much as 8 inches in the Charleston area. By 10 a.m., wind and rain had downed trees and powerlines in Summerville, James Island and Mount Pleasant. As winds hit 30 mph, Charleston County emergency managers have suspended shelter bus runs.? About 35,000 customers across South Carolina were without power at 10 a.m., utilities reported.

That didn’t stop some people from venturing out. In downtown Charleston, Jimmy O’Riordan used an umbrella and skateboard to sail down Columbus Street and “catch some great gusts.”

Meantime, the storm’s pull on the ocean remained fierce.

On Sunday, the storm drew water away with it as it left Florida’s Key West, leaving the seabed exposed in some areas. As the hurricane moved north, it pushed walls of water into Miami and Jacksonville.

By this morning, the storm-tossed sea off Sullivan’s Island and Folly Beach built waves into foamy castles. Whitecaps pounded the walls along East Battery, launching fountains of spray.

South Carolina’s Lowcountry is well-named, and a storm surge will affect a large swath of the state. More than 800 square miles of land lie less than 4 feet above the high tide line in South Carolina. And some $24 billion in property and 54,000 homes are in this area, a 2014 report by Climate Central found.

Storm surges affect some but not others. The Lowcountry is flat, but not evenly so. It’s full of subtle rises and dips, more like an old plaster wall instead of the uniform flatness of modern wallboard or Florida. This means surges can fill some of these dips with several feet of water, while a few yards away, the land might be dry.

MK Wildeman, Thad Moore, Gregory Yee, Bo Petersen and Prentiss Findlay of The Post and Courier staff contributed to this report.