An active 2023 hurricane season comes to a close

Updated November 30, 2023 at 2:46 PM ET

People on the Gulf Coast and along the Eastern Seaboard can breathe a little easier. The 2023 Atlantic hurricane season, which began June 1, ends today.

The season was above-normal in terms of activity. There were 20 named storms that formed in the Atlantic basin, starting with "Unnamed Storm" and ending with "Tammy." That's the fourth-highest number in a single year since 1950.

Seven of these storms turned into hurricanes and three of them became major hurricanes. The National Oceanic and Atmospheric Administration says an average season has 14 named storms, seven hurricanes and three major hurricanes.

Only one hurricane made landfall in the U.S. this year. Hurricane Idalia roared ashore on Florida's Gulf coast at the end of August. Although it was a Category 3 storm, damage was limited because it hit a sparsely populated section of the Florida coast.

The above-normal activity came in an El Niño year. That's a climate pattern that originates in the Pacific when warmer-than-usual ocean water affects the jet stream. El Niño is a phenomenon that usually suppresses Atlantic storms — but this year, meteorologists say unprecedented warm temperatures in the Atlantic, linked to climate change, fueled storm formation.

According to NOAA, more named storms formed in the Atlantic basin this year than in any other El Niño year in the modern record.

"The record-warm ocean temperatures in the Atlantic provided a strong counterbalance to the traditional El Niño impacts," says Matthew Rosencrans, with NOAA's Climate Prediction Center.

The Eastern Pacific also saw above average storm activity this year. Tropical storm Hilary hit Southern California in August, bringing heavy rain and flooding. As it approached, the National Hurricane Center issued its first-ever tropical storm watch and warning for southern California.

Last month, meteorologists were also surprised by the rapid intensification of Hurricane Otis, a Category 5 storm that slammed into Acapulco, Mexico.

The storm's sustained winds increased by 115 miles per hour in 24 hours as it approached the coast, reaching 165 mph at landfall. The National Hurricane Center says Otis was the strongest hurricane ever to make landfall in the Eastern Pacific in the modern era.

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