Updated

NASA scientists say an exceptionally powerful 2026 El Niño, which is intensifying rapidly, could grow larger than the historic 1997-98 event that brought extreme weather around the world. Using 35 years of satellite observations, NASA compared sea-surface height maps from October 1997 and October 2026 and found striking similarities, including a pronounced low-west, high-east sea level difference and warm water reaching the South American coast. That raises the possibility of heavy rainfall and flooding this winter, similar to what California and parts of the southern United States saw in 1997-98. Josh Willis, project scientist for sea level missions at NASA's Jet Propulsion Laboratory, said that "this one is on track to be even bigger." NASA also compared the event with the 2015-16 El Niño, which was also very strong but whose warm water did not extend as strongly toward South America, and whose rainfall fell mainly over Central America and the southeastern United States, with flooding in Mexico. Because no two El Niño events develop the same way, the article presents the similarities as a reason for concern rather than a firm forecast, and the exact impacts remain uncertain, the scientists said.