The death toll from Hurricane Helen has exceeded 150, with search teams using helicopters to weave through washed-out bridges and hiking through the wilderness to reach isolated homes.
Crews are still limping through knee-deep mud and debris in the wake of the deadly Category 4 storm that made landfall in Florida on Thursday and dumped more than 40 trillion gallons of rain across the southern United States. I was walking.
Precipitation is enough to fill Lake Tahoe, an Olympic-sized 200-foot pool with a depth of 1,645 feet and a surface area of 191 square miles. It could fill the Dallas Cowboys’ 80,000-seat stadium by more than 51,000 times.
“This is an astronomical amount of precipitation,” said Ed Clark, director of the National Oceanic and Atmospheric Administration (Noaa) Water Supply Center in Tuscaloosa, Alabama, according to the Associated Press.
Clark said the 40 trillion gallon estimate is rather conservative. And if this amount of water had fallen in the arid western states, it would have been enough to more than double Lake Powell and Lake Mead, he said.
The 40-ton-gallon calculation was made by meteorologist Ryan Maue, a former Noaa principal investigator, using precipitation measurements made on a 2.5-mile by 2.5-mile grid from satellite and ground-based observations.
“It wasn’t just a perfect storm, it was a combination of storms that dumped a lot of rain on high ground from 3,000 feet to 6,000 feet. And when you drop trillions of gallons down the mountain, it has to come down. No,” Maue told The Associated Press.
The measurements were taken during major floods that washed away entire towns in western North Carolina, Georgia, Tennessee, the Carolinas, and Florida.
“This storm brings a lot of rain and warm temperatures,” said North Carolina State Climatologist Kathy Dero. “There was a time when a tropical storm would come toward North Carolina and cause some rain and damage, but it wouldn’t have been catastrophic.”
Federal Emergency Management Agency (Fema) Director Deanne Criswell told CBS News on Sunday that Helen’s development took time. But once it started, Criswell said, it quickly gained momentum due to warming waters in the Gulf of Mexico due to the climate crisis, but largely due to humans burning fossil fuels.
Criswell said the impact is “more storms reaching this major category level than we’ve seen in the past.” He also said coastal areas were experiencing large amounts of destructive storm surge and “precipitation increases as we move north.”
“In the past, when looking at damage from hurricanes, it was mainly wind damage and some water damage, but now there is a lot of water damage, and I think that is due to the warm ocean. It’s a result of climate change,” Criswell added.
The hurricane occurred after a previous storm system passed through the area. The wreckage of Helen also stalled due to the low pressure.
Kristen Corbosiero, a hurricane expert at the University at Albany, told The Associated Press that Helen retained so much moisture because it was young and moved quickly before hitting the Appalachian Mountains.
It may take weeks to understand the damage from the storm. “This is a historic flooding level in an area where the topography cannot withstand that level of precipitation,” Janey Camp, a civil engineer at the University of Memphis, told Scientific American.
The region’s mountainous topography allows water to cascade quickly and pool in low-lying areas, increasing the risk of flooding.
“Unfortunately, this is a perfect storm for one of the worst possible situations,” Camp told the show.
More than 20 inches (51 centimeters) of rain fell in three days in the North Carolina area around Asheville, where the French Broad and Swannanoa rivers meet. For context, 8.4 inches in that period would be considered a 1-in-1,000-year event by metrics created before climate change.
Camp said local infrastructure is not designed to be resilient in a 1-in-100-year or even a 1-in-500-year situation. If so, “those design guidelines and standards were kind of thrown out the window.”
Authorities in North Carolina on Tuesday launched search and rescue operations in hopes of delivering aid and contacting hundreds of people stranded after Helen washed out roads and damaged cell phone towers, Reuters reported. We have resumed our activities.
More than 1.7 million homes and businesses in six states from Florida to West Virginia remained without power Tuesday.
