The Ubiquitous Floods and Floods During Category 5 Hurricanes in the Last Century: Transient Events in the Atlanta, South Carolina, and Tennessee

Scientists call a storm rapid-induction when it’s very powerful. It is not unusual for major hurricanes to form in the Atlantic. Ken Graham, the Director of the National Weather Service, said that Category 5 hurricanes in the last century were tropical storms three days earlier.

“The major ingredient that is present in virtually all of the rapidly intensifying events is an incredibly warm ocean surface,” explains Jill Trepanier, a hurricane climatologist at Louisiana State University.

Along with floods, the persistent rains have created landslide conditions in western North Carolina, as member station WFAE reported. The National Weather Prediction Center has forecast 6 to 12 inches for the region, well above the landslide condition threshold for the area.

The storm dumped more than 8 inches of rain in Wilmington and wrought serious damage to coastal homes and small buildings, as well as agricultural fields.

In North Carolina the rainfall totals were staggering: 29.58 inches for Busick, N.C., which is 55 miles away; 24.20 for nearby Mount Mitchell State Park, which is 65 miles away, and 13 inches in Boone.

Atlanta has gotten its highest 48-hour rainfall on record the past two days, due in part to heavy rains from Helene. The Georgia Climate Office tweeted on Friday that the area has already seen 11.12 inches of rain, beating a previous record of 9.59 set in 1886. Record keeping started in 1878.

In North Carolina, Helene produced unusually heavy winds — up to 140 mph — on land, the strongest observed in coastal North Carolina since the start of modern meteorological recordkeeping in the 19th century.

In Georgia, the death toll was 15, according to a spokesperson for Gov. Brian Kemp. At least two children were among the dead, reported local CBS station 13WMAZ. An emergency management official said that two Georgians died in Wheeler County when their trailer was picked up by a tornado.

The high winds and tornadoes were also blamed for several deaths. Gov. Ron DeSantis said one person died on a highway in Tampa from a falling sign. A tree fell on a home, killing another person.

A group of patients and staff were trapped on the roof of Unicoi County Hospital in Tennessee during the flooding on Friday morning. By the evening, they were rescued.

Meanwhile, the National Weather Service released an urgent warning through Friday afternoon urging anyone below the Lake Lure Dam near Ashville to evacuate immediately to higher ground, after concerns that the nearly century-old dam could fail.

Brigadier General Daniel Hibner with the Army Corps of Engineers said dam failures are to be expected in flash flooding events like this one. He said that a dam failure was not uncommon in an event like this. “I would be surprised if there weren’t multiple (dam failures) throughout this area.”

As of Friday evening, the dam remained intact. In a 6 p.m. ET update on social media, Rutherford County officials said the lake’s water levels were beginning to recede.

Florida’s 2020 Hurricane Laura: Flooding, Flooding and Flooding Prepared by a Category 4 Hurricane with Maximum Winds of 140 mph

More than 4 million homes and businesses were without power on Friday afternoon in Florida, Georgia, North Carolina and South Carolina, according to poweroutage.us. After nightfall, the number had dwindled to about 3.8 million.

For those relying on generators for power supply, the consumer safety officials advised people to keep them at least 20 feet away from the home to avoid deadly carbon monoxide poisoning. Improper portable generator use resulted in more deaths during 2020’s Hurricane Laura.

The surge was over 5 feet along the Gulf Coast of Florida. Andrew Swan was watching over a friend’s house when he rode out the storm. He told WUSF the water rushed into the house and he had to sleep on the kitchen counter with his legs over the stove.

Even though the worst of the storm is over for most people in the Southeast, officials want residents to remain alert for flooding and other dangerous conditions in the aftermath.

The National Weather Service said that the storm surge reached 15 feet above the ground in the Big Bend area near Steinhatchee and Horseshoe Beach.

In an evening update from the National Hurricane Center, maximum sustained winds were moving at 25 mph. The storm made landfall Thursday night in Florida’s Big Bend region — the nexus of the Panhandle and peninsula in the state’s northwest — as a Category 4 hurricane with maximum sustained winds of 140 mph.

The center said that there could be a lot of flooding over the Ohio and Tennessee Valleys.

Life-threatening flooding and landslides in parts of southern Appalachia were expected to continue into the evening, the National Hurricane Center said.

Helene weakened to a post-tropical cyclone on Friday evening but continued to unleash “catastrophic” flooding in the southeastern U.S. and southern Appalachians, forecasters said.