In the span of a little more than two days, abnormally warm waters quickly transformed Helene from thunderstorms and rain to a Category 4 hurricane, which meteorologists have attributed to global warming. Hurricanes are powerful tropical cyclones that form over warm ocean waters. These storms are characterized by intense wind speeds, heavy rainfall, and often accompanied by storm surges and coastal flooding. Hurricanes are among the most destructive natural phenomenas. Due to global warming, increases in sea surface temperatures play a critical role in fueling these storms. Global climate models predict hurricanes will likely cause more intense rainfall and have an increased coastal flood risk due to warmer, rising seas. Hurricane Helene emerged on September 23rd, 2024 as a region of scattered thunderstorms in the western Caribbean Sea, and by the next morning, meteorologists at the National Hurricane Center classified it as a tropical storm. Twenty-four hours later, Helene had strengthened to a Category 1 hurricane, with winds of 80 mph. 

Over the next 36 hours, Helene continued to gather strength from the unusually warm surface waters of the Gulf of Mexico, which were 84°F, nearly 1.8°F  warmer than the average temperature between 2003 and 2014. As it approached the Florida Panhandle at 8:00am on September 26th, Helene was reclassified as a Category 2 hurricane. Helene grew into a Category 3 hurricane by 2:25 pm and then a Category 4 hurricane by 6:20 pm, with sustained winds increasing from 100 mph to 130 mph in fewer than 10 hours.

Five hours after becoming a Category 4 storm, Helene slammed into Florida’s Big Bend region, 40 miles southeast of Tallahassee, with heavy rains and roaring winds that raged at 140 mph. It brought a 15-foot storm surge to nearby beachfront communities. Storm surge heights also ranged from about 6 to 8 feet in Tampa. Helene moved inland during the early morning hours of September 28, but at 5:00 am, with the storm’s center located over central Georgia, National Oceanic and Atmospheric Administration officials downgraded it to a tropical storm. However, some three hours later, Helene turned northwest, its center cutting across western North Carolina and eastern Tennessee. Although Helene’s winds had diminished to tropical-storm strength, the storm delivered a broad and deadly stream of heavy rain across the southeastern U.S. In parts of Florida, Georgia, North and South Carolina, Tennessee, and Virginia, record rainfall caused rivers to overflow and produce flash floods, road washouts, and even landslides.

The number of fatalities linked directly to Hurricane Helene had surpassed 300 people by October 7, with most attributed to flooding. As the storm traveled inland, it left a path of destruction nearly 500 miles long. Helene’s storm surge swept into ground floors of coastal residences and places of business, tearing apart hundreds of structures. It also drove boats, debris, and beach sand inland. Heavy rains and flooding washed out roads and bridges in Georgia, which saw the highest 48-hour rainfall totals on record. Knocked down power lines left around 4 million people without electricity. 

The flooding trapped thousands of people in their homes, requiring U.S. National Guard and municipal search-and-rescue teams to come to their aid using boats and helicopters. In Asheville, North Carolina, the effects of fast-moving water and mud cut several of the road and rail links to the town, and severed the pipes that connected Asheville’s water treatment plants from the mountains to the city. 

Roughly two weeks after Helene, several states in the disaster zone had begun to implement recovery plans, and repair crews worked to restore electrical power and repair damaged roads. Some estimates put the economic impact of the storm, including property and infrastructure damage, as high as $200 billion. Recovery efforts from the Biden-Harris administration continue to be underway, as well as help from local churches and organizations. As humans continue to emit greenhouse gasses into the atmosphere, who knows how many more dangerous hurricanes the future may hold. 

Information retrieved from cnn.com and washingtonpost.com