Hurricane Lee crossing the Atlantic Ocean as it moves westward on Sept. 8, 2023. Lee reached Category 5.
(CNN) -- The 2023 Atlantic hurricane season ends Thursday as one of the most active on record, with a twist: Most of its storms were diverted into the middle of the Atlantic Ocean.
But with El Niño expected to end next year and global temperatures to rise, forecasters say there's a "high potential" for an even more active hurricane season in 2024 and there's uncertainty about what that could mean for the United States.
Record ocean temperatures this season gave way to above-average tropical activity and neutralized the effectiveness of a strengthening El Niño, which normally inhibits the development of storms in the Atlantic by tearing them apart with hostile upper-level winds.
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By the end of the season, 20 named storms came to life, including seven hurricanes. Fortunately, only a fraction of these storms unleashed their fury on land.
Three Atlantic storms made landfall in the U.S.: Harold, Idalia and Ophelia. Idalia was the only hurricane to hit the U.S. this year when it hit Florida as a powerful Category 3 hurricane in August, becoming the strongest storm to hit that region of the state in more than 125 years.
The season with 20 named storms was the fourth-most in a single year since 1950, according to NOAA. Only the hyperactive hurricane seasons of 2020, 2005 and 2021 had more.
Fourteen named storms develop during an average Atlantic hurricane season, but when El Niño is strong, the number of named storms is usually smaller.
"The Atlantic basin produced the most named storms of any El Niño-influenced year in the modern record," Matthew Rosencrans, lead hurricane forecaster at NOAA's Climate Prediction Center, said in a news release.
Extremely warm ocean water also provided fuel for rapid intensification, causing some storms – including Idalia and Hurricane Lee – to explode with force. Lee peaked as a rare Category 5 hurricane in the open Atlantic after its winds increased to a staggering 136 km/h in 24 hours.
Since the season achieved so much tropical activity despite El Niño's best efforts to quell it, it is notable that most of these storms did not affect land.
When storms develop in the tropical Atlantic, it is the force of the Azores High (a large semi-permanent area of high pressure in the Atlantic off the northwest coast of Africa) that acts as a force field, pushing the storms westward toward the U.S. or away into the open Atlantic.
"When there's a really strong height, storms tend to keep moving westward or west-northwest into the Caribbean or through the Bahamas and into Florida or up the East Coast," Brian McNoldy, a senior research scientist at the University of Miami, told CNN.
But that wasn't the case this season, as the high pressure was quite weak due in part to record-breaking ocean temperatures, according to McNoldy. So many of the storms that developed in the tropical Atlantic followed the weakness of the high pressure and turned north, then moved northeast and deeper out to sea.
"Just that ingredient — record-breaking hot water — helped make hurricane season more active, but it also helped keep that activity away from land," McNoldy explained.
El Niño could disappear by next hurricane season
Hurricane experts say it's too early to tell if as many storms will avoid making landfall in the upcoming Atlantic hurricane season, but at least one thing is clear for the 2024 season: There will be no El Niño.
"The confidence that we're not going to have El Niño in the next hurricane season is pretty high, especially in August or September," Phil Klotzbach, a research scientist at Colorado State University, told CNN.
A strong El Niño cannot maintain its strength indefinitely and typically moves into a neutral pattern or even a weak La Niña the following year. Without El Niño to help limit storms, the model for the upcoming hurricane season could be quite different.
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"With the disappearance of El Niño, there is certainly the possibility of a more active season than normal, a relatively high potential," Klotzbach said. "If we hadn't had El Niño (this year), we certainly could have seen a season on par with 2020 or 2005."
But El Niño isn't the only factor that could change next year.
"The part we still have no idea about is how warm the Atlantic is going to be," McNoldy said.
Even if the fate of ocean temperatures next year remains uncertain, global temperatures will continue to rise due to human-caused climate change and will continue to put the oceans at risk of warming.
Given the uncertainty about ocean temperatures next year, the Azores High's peak strength and ability to steer storms toward the U.S. is also a "big question mark," according to Klotzbach.
"We'll see what happens next year, but it certainly has the potential to be quite interesting," Klotzbach said.
Rapid Intensification Dominates the Eastern Pacific Season
The 2023 eastern Pacific hurricane season also ends this Thursday and had several impactful storms, including two of the strongest hurricanes to make landfall on Mexico's Pacific coast.
The season's 17 named storms were more intense than average. Of those storms, 10 became hurricanes and several experienced rapid explosive intensification.
An aerial view of damage caused by Hurricane Otis in Puerto Marques, Guerrero state, Mexico, Oct. 28, 2023. (Rodrigo Oropeza/AFP/Getty Images)
Hurricane Otis was the most extreme example. Otis strengthened to a staggering speed of 185 km/h in 24 hours until its devastating Category 5 hurricane made landfall in Acapulco, Mexico.
Otis was the strongest Pacific storm ever to hit Mexico and came just two weeks after Category 4 Hurricane Lidia made landfall just south of Puerto Vallarta as another of Mexico's strongest Pacific storms.
Hurricane Hilary went through a period of rapid intensification that helped the storm maintain enough strength to pass through California as a tropical storm, the first in the state since 1997. Hilary unleashed a deluge of rain that broke tropical rainfall records in some states and caused extreme temperatures. floods that lasted for months in one of the driest places on Earth.
Earlier in the season, Hurricane Dora experienced rapid intensification as it moved south into Hawaii and contributed to strong winds that helped spark the catastrophic Lahaina Fire, the deadliest fire on U.S. soil in more than 100 years.