WASHINGTON — Federal weather officials are warning that this year’s El Niño is rapidly gaining strength and could reach historically powerful levels, with major implications for weather patterns across the country and around the world.
The U.S. National Oceanic and Atmospheric Administration released its monthly update Thursday, revealing that the current El Niño — a natural warming of equatorial Pacific Ocean waters that reshapes weather patterns globally — has an 81% chance of reaching “very strong” status, the highest category used, by this fall. If it does, it would rank among the most powerful El Niños recorded since tracking began in 1950.
El Niño works like a heat valve for the planet, releasing stored warmth from deep in the tropical Pacific into the atmosphere. Its most significant effects — including droughts, heavy rainfall, and heat waves — are expected to be felt most strongly during the fall and winter months.
The current El Niño formed just last month but has already advanced past the weak stage into moderate territory, with no signs of slowing down. Ocean temperatures in key Pacific regions that scientists use to measure El Niño strength are at or near record highs for this time of year. Experts say part of the reason is that this El Niño is developing on top of already elevated ocean temperatures driven by human-caused climate change.
“It’s pretty extreme,” said Emily Becker, a University of Miami scientist who works alongside the NOAA El Niño forecast team. “Not unprecedented, but very unusual.”
Becker said the current event could rival the powerful El Niño of 1997-1998, and some other meteorologists believe it could even surpass it. The World Bank has documented that the 1997 El Niño contributed to 23,000 deaths in weather-related disasters, pushed up poverty rates in several countries, and cost governments as much as $45 billion.
“This is not a run-of-the-mill El Nino,” said Daniel Swain, a climate scientist with the University of California Agriculture and Natural Resources. He noted that unlike previous super El Niños, this one is unfolding against a backdrop of significant global warming from the burning of fossil fuels. “We might not expect to see the exact same impacts from this event as we have seen in historical ones,” he said.
Becker clarified that a very strong El Niño — measured by Pacific Ocean temperatures — doesn’t automatically mean more extreme weather, but it does make such conditions more probable. For most of the southern United States, that means a higher likelihood of a wetter winter. Northern parts of the country and Canada, meanwhile, face increased odds of warmer-than-normal winter conditions.
One area where El Niño typically brings relief is the Atlantic hurricane season, which it tends to suppress. Colorado State University, which was a pioneer in seasonal hurricane forecasting, dramatically scaled back its storm predictions on Wednesday, citing “increased confidence in a strong or very strong El Niño.” The university’s forecasters now expect overall Atlantic hurricane activity to come in “well below normal.”
On a global scale, El Niño is expected to bring drier conditions to Indonesia and a warmer, wetter eastern Pacific region.
Swain described the broader climate role of El Niño in a blog post, writing: “El Niño also acts as a ‘thermostat’ for global climate by liberating years’ worth of accumulated heat stored in the subsurface tropical Pacific Ocean and dumping it into the atmosphere, where it eventually dissipates–but not before warming the entire planet in the meantime.”
Many climate scientists are now predicting that 2027 could shatter the global temperature record set in 2024 during the last strong El Niño event, as pent-up heat is eventually released.
“A strong El Niño would raise the odds of dramatic new climate records over the next 6 to 12 months,” said Zack Labe, a climate scientist at Climate Central. He added that the event could offer a preview of an even hotter world in the years ahead.
