Hurricane Helene: How Climate Change Fueled One of the Deadliest Storms in Recent History

Late September 26th, Hurricane Helene made landfall in Florida as a Category 4 storm, bringing devastating winds, torrential rainfall, and deadly storm surges. Over the next two days, the storm mapped a destructive path going inland through Georgia and moving through the Carolinas, Tennessee, and Virginia, causing unprecedented flooding, widespread power outages, and the loss of over 227 lives. The aftermath of Hurricane Helene was one of the deadliest and most destructive hurricane impacts the U.S. had seen since Hurricane Katrina in 2005.

But what made Hurricane Helene so catastrophic? Scientists believe that climate change played a significant role, intensifying the storm’s winds and rainfall and creating the environmental conditions that fueled its power. A new analysis by the World Weather Attribution group reveals that human-caused global warming made last month’s Hurricane Helene 200 to 500 times more likely. Climate change increased Helene’s rainfall by 10% and intensified its winds by 11% (around 13 mph). The analysis revealed that fossil fuel burning has made storms as severe as Helene 2.5 times more likely than in the pre-industrial era. The researchers said that if global warming reaches 2°C above pre-industrial levels, storms like Helene could bring 10% more rainfall unless significant emission cuts are made. 

Climate Change’s Influence on Hurricane Helene

The formation and progression of Hurricane Helene were influenced by several factors linked directly to climate change- particularly warming sea surface temperatures (SSTs) in the Gulf of Mexico. Record-high SSTs fueled the storm’s strength, providing the energy required to sustain its intense winds and rainfall. According to an international team of scientists from the U.S., U.K., Sweden, and the Netherlands, the SSTs along Helene’s track were made 200-500 times more likely due to human-induced global warming. This warming has increased average global temperatures by 1.3°C, primarily due to burning fossil fuels.

The scientists studied how climate change impacted different aspects of Helene, focusing on its rainfall, wind speeds, and the overall environmental conditions that boosted its destructive potential. Their findings indicate that climate change increased Helene’s rainfall by about 10%. In comparison, extreme rain events became 40% more likely in coastal areas and 70% more likely inland. 

The inland devastation was particularly severe. Before Helene’s arrival, a stalled cold front combined with moisture from the storm’s outer bands to trigger heavy rainfall. This pre-hurricane deluge set the stage for catastrophic flash flooding once Helene’s full force reached the Southern Appalachians. The heavy rain and the region’s steep terrain funnelled floodwaters into rivers and streams, causing flash floods that rose to rooftop levels and overwhelming evacuation efforts.

Wind Intensification and Rapid Storm Formation

Climate change also intensified Hurricane Helene’s wind speeds. Statistical models suggest that similar storms used to occur once every 130 years; now, due to global warming, they happen every 53 years on average. Climate change increased Helene’s maximum wind speeds by approximately 11%, leading to more robust and destructive gusts at landfall.

The storm’s rapid intensification, another hallmark of climate-driven hurricanes, was directly linked to record-high SSTs. Such rapid intensification has become more common in Atlantic tropical cyclones under current climate conditions. The researchers found that the environmental factors contributing to Helene’s strength, such as high SSTs, air temperature, and humidity, were amplified by climate change, making the storm’s potential intensity 18 times more likely.

Future Threats and Infrastructure Challenges

The findings suggest a worrying future: if global warming continues and the world reaches 2°C above pre-industrial levels, storms like Helene could become 15-25% more likely. This underscores the urgent need for climate action to mitigate future catastrophic hurricane events.

In addition to the extreme weather, the inland regions impacted by Hurricane Helene faced infrastructure challenges that worsened the disaster. Inadequate evacuation plans, spotty communication networks, and ageing flood control systems—particularly dams and drainage infrastructure—left many communities vulnerable. Though dam failures were narrowly avoided, the widespread flooding overwhelmed current protective measures, revealing the critical need to upgrade infrastructure in regions increasingly exposed to climate-driven disasters.

Hurricane Helene’s catastrophic impact was not just the result of a natural disaster—it was boosted by human-induced climate change. Warmer oceans, more intense rainfalls, and stronger winds contributed to the storm’s unprecedented destruction. The tragic loss of life and widespread destruction across the Southeast US should serve as a reminder that climate change is no longer a distant threat. 

Reference:

https://www.worldweatherattribution.org/climate-change-key-driver-of-catastrophic-impacts-of-hurricane-helene-that-devastated-both-coastal-and-inland-communities/ 

Banner Image: Hurricane Helene in the Gulf of Mexico on September 25. Image by NOAA’s GOES-16 satellite.