Forecasters had predicted Hurricane Helene would be a “once-in-a-generation” storm, and tragically, their warnings came to fruition as the storm ravaged parts of the Appalachians, resulting in widespread devastation across western North Carolina, eastern Tennessee, South Carolina, and Georgia. As of Monday, dozens of fatalities have been confirmed, with hundreds of individuals reported missing, and damage estimates soaring into the tens of billions of dollars.
The torrential rain preceding and during the storm led to what Corey Davis, North Carolina’s assistant state climatologist, described as “the most severe flooding ever observed” in the region. The catastrophic flooding was attributed to a combination of factors, including weather patterns, hydrology, and the unique geography of the area.
Over a stretch of more than 200 miles, record rainfall transformed mountain streams into raging torrents, flooding valleys and isolating communities. In East Tennessee, one hospital found itself completely surrounded by floodwaters.
The storm’s impact was intensified by a stalled weather front that had lingered over the Appalachians before Helene’s arrival. Rainfall was already being reported in the mountains as early as Wednesday, September 25, when Hurricane Helene was still a Category 1 storm located far from the coast of Florida.
As Helene made its way toward the Southeast, it tapped into tropical moisture from the Gulf of Mexico, leading to rainfall amounts of 6 to 30 inches across parts of North Georgia, western North Carolina, eastern Tennessee, and into Virginia over the course of three days.
The mountainous terrain contributed to the severe flooding, with steep slopes and shallow soil unable to absorb the intense rainfall. Russ Barton from NOAA’s National Water Center highlighted that most infrastructure is situated in the valleys, which acted as natural channels for the floodwaters.
The flooding has been compounded by high winds, which toppled trees and downed power lines, while mudslides and landslides exacerbated the situation, taking out roads and entire homes. “There’s no telling how much loss of life there has been,” Barton stated.
In Lake Lure, North Carolina, known for its picturesque scenery, U.S. Geological Survey data revealed that the flow in Cove Creek surged by an astounding 32 times in just 48 hours. The French Broad River in Asheville recorded 12 inches of rain over three days, with flow levels increasing by 20 times, leading to a muddy torrent flowing at over 240,000 gallons per second—enough to fill an Olympic-sized swimming pool every 2.74 seconds.
As rescue and recovery efforts continue, the full extent of the damage remains to be seen, as communities begin to grapple with the aftermath of this unprecedented storm.
