El Niño is a band of warm water that typically leads to higher wind shear over the Atlantic—basically, winds that change as you change altitude. And hurricanes don’t appreciate wind shear. “Hurricanes, in a perfect world, don't like winds to change with height—the top is moving at the same speed and direction as the bottom of it, and then it's happy,” McNoldy says. 

That means it’s a race against atmospheric time: Will the additional heat in the Atlantic fuel more hurricanes, or will El Niño butt in promptly and provide the wind shear that prevents those storms from spinning up? Hurricane season runs through the end of November. This year’s El Niño began in June and is expected to ramp up over the year—this atmospheric phenomenon typically peaks between November and February. If El Niño doesn’t intensify much until winter, it’ll be too late for it to suppress storm activity during the majority of hurricane season. That could mean not only more hurricanes, but stronger ones.

So far, that trajectory isn’t clear. But this June has already seen two named tropical storms in the Atlantic: Bret and Cindy. (Tropical storms have sustained winds of between 39 and 73 miles per hour, while a hurricane is 74 miles per hour and above.) “That is weird—very weird. Normally, you don't start seeing that sort of activity until mid-August,” says McNoldy. “The ocean temperatures are still a little on the cool side normally, and there's a lot of Saharan dry air that is coming off the continent. And hurricanes don't like cool water or dry air. So normally right now those two things are keeping that part of the Atlantic in check.”

And those aren’t the only X factors scientists have to contend with. To put it bluntly: The world’s oceans are super weird and extra hot this year. The graph below shows average global sea surface temperatures (not just for the North Atlantic), with 2023 marked in the thick black line. They’ve been smashing records since March.