Over 40 Trillion Gallons of Rainfall: Hurricane Helene and Storms Devastate the Southeast
In a staggering weather event, more than 40 trillion gallons of rain inundated the Southeast United States over the past week, resulting from Hurricane Helene and an ordinary rainstorm that preceded it. This unprecedented deluge has left experts and meteorologists in disbelief.
To put this immense volume into perspective, the rainfall is equivalent to filling Dallas Cowboys’ AT&T Stadium 51,000 times or Lake Tahoe just once. If the rainfall were concentrated solely on North Carolina, it would cover the ground to a depth of 3.5 feet (over 1 meter)—enough water to fill over 60 million Olympic-sized swimming pools.
“This is an astronomical amount of precipitation,” stated Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “In my 25 years at the weather service, I have never witnessed such a geographically extensive event with this sheer volume of rain.”
The aftermath of the storm has been devastating, with reports indicating that over 100 people have lost their lives due to the flooding. Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated that the eastern United States received 40 trillion gallons of rain through Sunday, with 20 trillion gallons concentrated in Georgia, Tennessee, the Carolinas, and Florida from Hurricane Helene alone.
According to Clark, the rainfall figure of 40 trillion gallons (151 trillion liters) is likely conservative, with Maue suggesting that 1 to 2 trillion additional gallons may have fallen, particularly in Virginia. Notably, this volume surpasses the total water stored in key Colorado River basin reservoirs, including Lake Powell and Lake Mead, combined.
Meteorologists have noted that the extreme rainfall resulted from a combination of several storm systems. Before Helene made landfall, a low-pressure system had stalled over the Southeast, allowing for continuous heavy rainfall and funneling warm water from the Gulf of Mexico. Additionally, a storm that did not reach named status parked off the North Carolina coast, dropping as much as 20 inches of rain, according to state climatologist Kathie Dello.
Hurricane Helene, one of the most significant storms in recent decades, brought an immense amount of rain due to its youth and rapid movement before striking the Appalachians. “It wasn’t just a perfect storm; it was a combination of multiple storms that contributed to this extraordinary rainfall,” said Maue.
The geographical impact was exacerbated by the mountainous terrain, which increases moisture extraction from the atmosphere. According to meteorologists, the highest recorded rainfall in North Carolina was 31.33 inches in the small town of Busick, while Mount Mitchell received over 2 feet of rain.
Reflecting on past storms, Clark remarked, “Before Hurricane Harvey in 2017, I never thought we’d measure rainfall in feet. Now, we see events year after year where rainfall is measured in feet.”
The prevailing trend indicates that storms are becoming wetter due to climate change, with experts stating that warmer air holds nearly 4% more moisture for every degree Fahrenheit increase. Given that the world has warmed over 2 degrees Fahrenheit since pre-industrial times, the implications for weather patterns are significant.
Debates among meteorologists continue regarding the extent to which climate change has influenced Hurricane Helene’s rainfall. A quick analysis from scientists at the Lawrence Berkeley National Lab suggested that climate change resulted in 50% more rainfall in certain regions of Georgia and the Carolinas during Helene. Dello emphasized that the “fingerprints of climate change” are evident in the intensity and frequency of such storms.
“We’ve observed tropical storm impacts in western North Carolina,” Dello noted. “But these storms are now both wetter and warmer. In the past, a tropical storm would have brought some rain and damage, but nothing compared to the apocalyptic destruction we’ve seen today.”
Source: AP
