A week after Hurricane Paulette hit Bermuda and subsequently weakened as it spun north in the Atlantic Ocean, the system has come back to life as a “zombie” tropical storm, according to the National Oceanic and Atmospheric Administration.
NOAA’s National Hurricane Center issued an advisory late Monday saying Tropical Storm Paulette had reformed southeast of the Azores, a series of islands off the coast of Portugal. At the time, the storm had maximum sustained winds of 60 miles per hour.
It’s not the first time that NOAA has observed a storm coming back to life, but experts said it’s still an unusual phenomenon — and one that comes amid an extremely busy hurricane season in a year that has been chock full of extremes.
“It’s not unprecedented, but it’s not something we see very often, and it kind of fits this year of weird, weird things happening,” said Phil Klotzbach, an atmospheric scientist at Colorado State University in Fort Collins.
The National Weather Service also referred to the odd nature of the storm’s return, tweeting Tuesday: “Because 2020, we now have Zombie Tropical Storms. Welcome back to the land of the living, Tropical Storm #Paulette.”
Paulette originally formed in early September and made landfall in Bermuda on Sept. 14 as a Category 1 hurricane. The storm strengthened to a Category 2 as it passed over the island, but it eventually moved northeast into open waters and was downgraded into a “post-tropical cyclone” on Sept. 16. This classification is used to describe storms systems that no longer have the characteristics that define a tropical cyclone.
Storms that migrate into the North Atlantic Ocean normally fizzle out as they hit colder water, according to Jeff Weber, a meteorologist at the University Corporation for Atmospheric Research, a nonprofit consortium of more than 100 universities and colleges in Boulder, Colorado. In this case, however, Paulette bumped into a high-pressure trough in the mid-Atlantic that pushed the storm south, where it encountered warm water that enabled it to reform as a tropical storm.
“For this system to dive that far south and regain its tropical characteristics — that’s the unusual aspect here,” Weber said.
Scientists have recorded other instances of hurricanes that have reformed as zombie tropical storms, according to Klotzbach. The most recent example is Ivan, which ploughed through the Caribbean and made landfall as a Category 3 hurricane near Gulf Shores, Alabama, in September 2004. The storm subsequently weakened as it moved into the subtropical Atlantic but respawned as a tropical cyclone and hit the southeastern United States again later that month.
“If you go back in the historical record, there have been storms that have done some weird things,” Klotzbach said. “Certainly Paulette joins that list now.”
Though climate change is making hurricanes more intense, and therefore more destructive, Klotzbach said global warming is likely not squarely to blame for the return of Paulette.
But, it’s possible that warming oceans due to climate change could make zombie storms more common in the future, according to Weber, since warmer oceans “will be able to support tropical development over larger areas of the Atlantic.”
But for all the drama of Paulette’s rebirth, the storm’s second life is not expected to last very long. The system had already weakened as of Tuesday morning, with maximum sustained winds of 40 mph, and the storm is projected to further degrade.
“Additional weakening is forecast to take place, and Paulette is expected to become a remnant low within the next day or so,” Dennis Feltgen, a meteorologist and spokesperson for the National Hurricane Center, said in an email.