The 2025 hurricane season was a study in contrasts.
In one way, it felt very quiet in the United States. No storms made landfall in the U.S. for the first time since 2015. And, for about three weeks in the middle of the hurricane season, no storms formed at all in the Atlantic.
And yet, the storms that did form were among the most powerful hurricanes ever recorded.
"The one word I would pick for it is 'unusual'," says Brian McNoldy, a hurricane researcher at the University of Miami. In 2025, the total number of tropical storms and hurricanes, 13, was about average. But a lot of those storms ended up being massive Category 5 behemoths.
"We had three Category five hurricanes this year, which is the second most in a single season behind only the super hyperactive 2005 season," says Lindsey Long, a meteorologist with the Climate Prediction Center at the National Oceanic and Atmospheric Administration. The infamous 2005 Atlantic hurricane season included hurricanes Katrina, Rita and Wilma. The fact that none of this year's storms made landfall in the U.S. was just luck, Long says.
Years like this one, with an average number of overall storms, but an above-average cohort of very powerful hurricanes, are getting more likely because of climate change.
That's mainly because global warming is causing ocean temperatures to rise dramatically. Planet-warming pollution — most of which comes from burning oil, gas and coal — traps huge amounts of extra heat in the atmosphere. Most of that extra heat is absorbed by the oceans.
The part of the Atlantic ocean where hurricanes form has experienced record-breaking heat over the last few years.
"That water is kind of fuel for hurricanes," Long says. "It helps dictate how intense the storm will be."
That's what happened this year with Hurricane Melissa. The storm moved over abnormally warm water as it gained strength, ultimately making landfall in Jamaica as a devastating Category 5 hurricane in late October. The Atlantic hurricane season extends from June 1 to Nov. 30.
At the same time, wind patterns can break storms apart. Wind shear, which happens when there's a big difference in wind speed high in the atmosphere versus down lower, makes it difficult for storms to form. Long says there was quite a bit of wind shear this year, which kept the total number of storms average.
Climate computer models suggest that there will be more wind shear in the part of the Atlantic where hurricanes form as the Earth continues to warm.
Taken together, that means a hotter planet will likely mean fewer total hurricanes, but higher percentage will be large, powerful storms.
The 2025 season "happens to fit that mold extremely well," McNoldy says.
Not every hurricane season will look like this. Even though the climate is steadily warming, and ocean temperatures are consistently above-average in the Atlantic, there's still a lot of variability in how many storms form and how powerful they get in any given year.
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