The storm is intensifying as expected as it enters the southern Gulf of Mexico. A sharp upper-level trough digging over the southern U.S. is picking up the storm and forcing it to turn north-northeast and accelerate toward the Florida Panhandle.
- 100+ mph winds will hit the Florida Panhandle as Helene makes landfall, with long-lasting power outages and a life-threatening storm surge across the region
- Damaging winds will push toward Atlanta, Greenville, and Charlotte, with a threat for widespread power outages
- Extensive flooding rains will continue into Friday, especially through northern Georgia, upstate South Carolina, and western North Carolina
- Tornadoes are possible in the storm's outer rainbands through Friday
Here's the latest on the storm and its predicted impacts.
Helene Strengthening
Helene is quickly strengthening as it encounters a very favorable environment around the storm. Sea surface temperatures in the southern Gulf of Mexico are on the order of 88-90°F. That upper-level trough is also helping to vent air up and away from the storm; this kind of efficient outflow can help storms thrive.
It can't be overstated that this is a large hurricane. Helene's minimum central pressure is 978 mb, which is very low for a hurricane of this strength. Storms can translate some of that energy into growing their size—exactly what Helene is doing now.
As of 5:00 p.m. EDT on Wednesday, tropical storm force winds extended 345 miles from the center of the storm. This broad size will continue to grow and exacerbate the storm's impacts across the southeast as it pushes inland through the end of the week.
Landfall on Thursday Evening
Forecasters with the National Hurricane Center continue to expect Helene to strengthen into a major category four hurricane as it powers toward the Florida Panhandle over the next 24 hours, where the storm will likely make landfall on Thursday evening. A life-threatening storm surge of 15-20 feet is possible across Florida's Big Bend if the storm arrives at high tide—an exceptional potential that's due both to the storm's intensity and sheer size.
Sustained winds of 100+ mph will buffet a large swath of the Florida Panhandle as Helene's eyewall pushes ashore. These winds could bring significant structural, tree, and power line damage to the Tallahassee area. Communities affected by the eyewall could go a week or longer without electricity.
Major Inland Wind Impacts Expected
From there, the large storm will push into Georgia and the western Carolinas overnight Thursday and into the day Friday.
Helene's enormity and swift forward speed will prevent the storm from quickly weakening after it makes landfall. Sustained winds of 75+ mph are likely well into southern Georgia, where hurricane warnings are in effect.
The system will likely remain a potent tropical storm into the day Friday as it makes its way into northern Georgia. A tropical storm warning is in effect for the cities of Atlanta, Greenville, and Charlotte ahead of Helene's arrival.
Sustained winds of 40-60 mph, with higher gusts, could bring widespread tree damage and long-lasting power outages to northern Georgia—including the Atlanta metro area—as well as upstate South Carolina and western North Carolina.
Life-Threatening Flash Flooding Likely
We'll have to deal with prolific rains on top of the threat for widespread wind damage. Heavy rain will start Wednesday night, well in advance of the storm's arrival. Significant flash flooding is likely throughout Georgia, western South Carolina, and western North Carolina for the duration of this storm, where 7-10+ inches of rain could fall through Friday.
The southern Blue Ridge remains under a high risk for excessive rainfall through Friday, which signals extreme confidence among meteorologists that major flash flooding will occur throughout the region. Flash flooding is possible across areas that may not typically flood. Landslides and road washouts are likely in vulnerable areas.
Tornado Threat
On top of all the other hazards, we have to remain alert for the risk for tornadoes on the eastern half of the storm. Strong wind shear in the eastern half of landfalling tropical cyclones can produce a risk for tornadoes. Tropical tornadoes can happen quickly with reduced tornado warning lead time.
The greatest risk for tornadoes on Thursday will fall across northern Florida and eastern sections of Georgia and South Carolina. We'll see the threat for tornadoes focus on North Carolina and portions of South Carolina and Virginia heading into the day Friday.
NHC Updates
The National Hurricane Center releases full forecast packages—including updated cones and wind forecasts every six hours, at 11:00 a.m./p.m. and 5:00 a.m./p.m.
When there are watches and warnings in effect, the agency also releases intermediate updates every three hours in between. These advisories provide status updates on the storm's current location and conditions, as well as any changes to watches and warnings that are in effect.
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