Hurricanes, large and small, have eluded U.S. shores for record lengths of time. As population and wealth along parts of the U.S. coast have exploded since the last stormy period, experts dread the potential damage and harm once the drought ends.
Three historically unprecedented droughts in landfalling U.S. hurricanes are presently active.
A major hurricane hasn’t hit the U.S. Gulf or East Coast in more than a decade. A major hurricane is one containing maximum sustained winds of at least 111 mph and classified as Category 3 or higher on the 1-5 Saffir-Simpson wind scale. (Hurricane Sandy had transitioned to a post tropical storm when it struck New Jersey in 2012, and was no longer classified as a hurricane at landfall, though it had winds equivalent to a Category 1 storm.) The streak has reached 3,937 days, longer than any previous drought by nearly two years.
Twenty-seven major hurricanes have occurred in the Atlantic Ocean basin since the last one, Wilma, struck Florida in 2005. The odds of this are 1 in 2,300, according to Phil Klotzbach, a hurricane researcher from Colorado State University.
Florida hasn’t seen a hurricane of any intensity since 2005’s Wilma, which is shocking considering it averages about seven hurricane landfalls per decade. The current drought in the Sunshine State, nearing 11 years, is almost twice as long as the previous longest drought of six years (from 1979-1985).
Sixty-seven hurricanes have tracked through the Atlantic since Florida’s last hurricane impact. The odds of this are about 1 in 550, Klotzbach said.
Even the entire Gulf of Mexico, and its sprawling coast from Florida to Texas, have been hurricane-free for almost three full years, the longest period since record-keeping began 165 years ago (in 1851). The last hurricane to traverse the Gulf waters was Ingrid, which made landfall in Mexico as a tropical storm, in September 2013.
Scientists have no solid explanation for the lack of hurricane landfalls. The number of storms forming in the Atlantic over the past decade or so has been close to normal, but many have remained over the ocean or hit other countries rather than the United States.
A study published by the American Geophysical Union in 2015 said the lack of major hurricane landfalls boiled down to dumb luck rather than a particular weather pattern. “I don’t believe there is a major regime shift that’s protecting the U.S.,” said study lead author Timothy Hall from NASA.
A “recurring” area of low pressure near the U.S. East Coast in recent years may have repelled some storms, argue Klotzbach and Brian McNoldy, a hurricane researcher at the University of Miami. But McNoldy still says “luck is really 99 percent of it [the drought].”
Adam Sobel, a climate scientist at Columbia University, cautions that the drought in no way invalidates global warming predictions or the expectation that storms will grow more intense in future decades. The “notion that the hurricane drought in the Atlantic has somehow disproved the consensus projections of climate science is wrong, because the drought is still a relatively short-term fluctuation in a single basin, while the projections are for long-term global trends,” he writes on his blog.
And as impressively long as the various droughts are, McNoldy said there have been numerous storms that have almost ended each of them in recent years.
So the drought is hanging on by a thread. A single major hurricane striking Florida’s Gulf Coast, McNoldy said, would break all three standing droughts simultaneously.
Concerns about preparedness and increasing coastal population
It’s only a matter of time before the luck reverses and storms start bombarding the U.S. coast again.
Growing coastal populations and lack of recent hurricane activity, from Florida to Texas, raise concerns about the nation’s readiness.
“Hurricanes are going to hit the U.S. again and people are going to be shocked by the magnitude of the disaster,” said Roger Pielke Jr., professor of environmental studies at the University of Colorado at Boulder.
The Associated Press reports Florida’s coastal communities have added 1.5 million people and almost a half-million new homes since 2005, the last time there was an onslaught of storms.
The National Oceanic and Atmospheric Administration projects that by 2020, the U.S. coastal population will have reached 134 million people, 11 million more than in 2010.
“Hurricane damage and destruction is a direct function of how much accumulated wealth there is,” Pielke said. “We’ve put a lot of stuff along the coast. If we’re in this 10-year drought, loss potentials in some places may now be two times higher than it was a decade ago.”
Experts are conflicted as to whether residents — after a long break from dealing with hurricanes — will be well-prepared when the next storm threatens.
Kim Klockow, a visiting scientist with NOAA who studies meteorology and social behavior, said one major concern “is that communities might not be as practiced in getting prepared simply because they haven’t had to do it in a while.”
But she said she doesn’t think residents will tune the storm threat out. “I’m not sure if the long period of calm will make them less concerned,” Klockow added.
Gina Eosco, a social scientist who works with National Weather Service through the consulting firm Eastern Research Group, agrees with Klockow. “Coastal residents are savvy,” she said. “They understand that by living on the coast they are taking some risk. An individual does not necessarily need direct experience to decide to evacuate or prepare for a hurricane.”
Still, Pielke said consequences are inevitable for out-of-practice communities. “You can do all the talking and planning you want, but until you go through a hurricane, you don’t know what you’re up against,” he said. “The lessons of inexperience are pretty costly.”
Eosco offered this advice: “I cannot overstate the importance of preparing before a storm happens. This starts with a conversation. Each resident with experience should share it with their new neighbors.”
Brian McNoldy and Phil Klotzbach contributed to this post.