- Areas outside the forecast cone of Hurricane Helene must prepare for widespread impacts.
- Flooding and storm damage will extend well beyond the forecast cone of the storm.
- Outside the cone, storm surges of up to 15 feet are possible.
Hurricane Helene is not only a strong storm, it’s a big one too – and its size and strength are only expected to increase. That means wind, rain and damage will extend well beyond the forecast cone.
“The National Hurricane Center’s forecast cone was never intended to capture all of the impacts of a hurricane,” explains Jon Erdman, meteorologist at weather.com. “It simply shows where there is a two-thirds probability that the center of the storm will be.”
(MORE: Hurricane Helene forecast | Map Tracker)
This storm could carry a tropical storm-force wind field hundreds of miles wide, making it more important than ever to focus on the impacts of Helene, not the cone.
Because the storm is so large, it will act like a bowling ball rolling toward the coast, taking a lot of momentum inland with it. The storm will be able to maintain its intensity as it moves inland, and could still develop into a hurricane by the time it reaches southern Georgia.
Wind hazard: The National Hurricane Center predicts that Helene’s tropical storm-force winds will be as far away as 200 miles from the storm’s center. This means that if Helene makes landfall in the Big Bend region of Florida, the tropical storm-force winds could spread across much of the state, including locations to the south. The further inland Helene moves, the stronger the winds will become.
“Another important factor is that this large hurricane is moving faster both before and after its landfall,” Erdman said. “This means its strong winds will reach farther inland than a slow-moving hurricane.”
Hurricane-force winds could reach southern Georgia overnight into Thursday, and at least some tropical storm-force gusts could occur in much of Georgia (including Atlanta) and parts of South Carolina through Friday.
This will cause trees to fall and possibly widespread power outages.
Flood risk: The concern about flooding will also extend far beyond the forecast cone.
“Added to this threat is a so-called ‘predecessor’ rain event that will bring heavy rainfall to the southern Appalachians well before Helene’s arrival between Wednesday evening and Thursday,” Erdman explained.
The Weather Prediction Center has already warned of a rare “high” risk of flooding for parts of the Appalachian Mountains due to rain expected on Wednesday. This includes parts of western North Carolina, northern Georgia and upstate South Carolina; a region highly prone to flooding. Once the previous rain has cleared, Helene will come right in, creating a perfect storm with flooding potential.
There is also a risk of flooding in much of the Southeast, from western Tennessee to the Atlantic coast, where up to 30 centimeters of rain could fall.
“Helene is a prime example of how hurricanes are not just coastal events,” Erdman said.
Storm surge: Storm surge will also be a major concern along the coast outside the forecast cone. Florida’s Big Bend could see storm surges of up to 15 feet, and Tampa Bay could see storm surges of 5 to 8 feet. Storm surge is expected along the entire west coast of Florida.
While Helene will record the highest storm surge east of where the storm makes landfall, a significant rise in water levels is also likely outside the cone.
