FILE: Great Smoky Mountains National Park in the fall. (NPS / FOX Weather)
null - While Florida braces for Hurricane Helene, the size of the storm means widespread impacts will be felt across the eastern U.S. late this week, including damaging winds, flooding rain and possible tornadoes in states well into the Southeast, mid-Atlantic and Midwest after landfall.
On its current track, the National Hurricane Center (NHC) said Hurricane Helene is forecast to make landfall along the Florida Big Bend on Thursday evening as a Category 4 hurricane with winds of at least 130 mph. After landfall, Helene is forecast to slow down and turn northwest, moving over the Southeast through Friday and Saturday.
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The large storm will bring widespread heavy rain, damaging winds and possible tornadoes to cities in the Southeast, including Atlanta and Asheville, North Carolina. Ahead of those impacts, the governors of Georgia, South Carolina and North Carolina have declared states of emergency.
Helene wind forecast for the Southeast. (FOX Weather)
Atlanta is under a Tropical Storm Warning, meaning it could experience tropical storm conditions just hours after Helene's landfall.
Tropical-storm-force winds will be felt in South Carolina as soon as Thursday and across the Southeast through Saturday, with peak gusts up to hurricane strength in parts of Georgia and South Carolina. Helene is expected to track northwest into Kentucky and Tennessee, bringing gusty winds of up to 70 mph.
The NHC is also warning a tornado or two may occur Wednesday in parts of the western Florida Peninsula and southern Alabama. The risk of tornadoes will increase Thursday, expanding across Florida and into parts of Georgia and South Carolina.
Significant to catastrophic flooding possible through this weekend
The biggest implications for Helene post-landfall will be the rain totals forecast across multiple states from Georgia to Kentucky and Virginia as Helene taps into available moisture in the Southeast and pushes toward the Appalachian Mountains.
"This will be one of the most significant weather events to happen in the western portions of the area in the modern era," the National Weather Service in Greenville-Spartanburg, South Carolina, said on Thursday.
Forecasters expect catastrophic flooding and landslides from Hurricane Helene, especially near the mountains and foothills in the Carolinas.
Available moisture in the Appalachians. (FOX Weather)
The NHC is warning of total rain accumulations of 5-10 inches with isolated totals near 15 inches. Cities such as Atlanta and Augusta in Georgia and Knoxville and Chattanooga in Tennessee are among those at the greatest flash flooding risk over the next five days.
"Catastrophic and life-threatening flash and urban flooding, including landslides, is expected across portions of the southern Appalachians through Friday," NHC forecasters wrote in a discussion about Helene. "Considerable to locally catastrophic flash and urban flooding is likely for northwestern and northern Florida and the Southeast through Friday. Widespread minor to moderate river flooding is likely, and isolated major river flooding is possible."
Forecast rain totals. (FOX Weather)
National Weather Service offices across the Southeast, including Greenville, South Carolina, are issuing Flood Watches and Warnings to warn residents of potentially catastrophic flooding. Ahead of Helene's rainfall, the region is expected to get several inches of rain from thunderstorms.
Flash flood outlook for Thursday. (FOX Weather)
Prepare for travel delays
Travelers should also prepare for delays through the weekend. Atlanta International Airport is warning airline travelers that the impacts could have a ripple effect across the Southeast.
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