NOAA confirms El Niño has formed, forecasts 63% chance of historically strong event

NOAA's Climate Prediction Center confirmed Thursday that El Niño conditions have developed in the equatorial Pacific, with forecasters giving 100% odds of the pattern continuing through fall and very high odds of it persisting into winter. The agency placed a 63% probability on the event reaching "very strong" intensity — colloquially called a "Super El Niño" — which would rank it among the largest since record-keeping began in 1950.

El Niño is driven by a periodic warming of the central and eastern tropical Pacific Ocean, which alters wind patterns and triggers weather shifts around the globe. CNN reported that large volumes of unusually warm water have been moving from the western to the eastern tropical Pacific over recent months, traveling 600 to 1,000 feet below the ocean surface before rising near South America — dynamics that have appeared in past intense El Niño events. For the event to qualify as a Super El Niño, tropical Pacific water temperatures must exceed 2 degrees above average; some computer models suggest that threshold could be significantly exceeded, CNN noted.

Princeton University climate scientist Gabriel Vecchi told the Associated Press that the early indicators — including warmer water pushing toward the Pacific surface — have been unusually consistent, with forecasters converging on an ultra-strong prediction at a time when El Niño forecasts typically show wide disagreement. Columbia University climate scientist Muhammad Azhar Ehsan said his team forecasts the event will peak one to two months earlier than usual based on strong early signals. Super El Niño events are relatively rare, with the most recent occurring in 2015-16, 1997-98, and 1982-83, according to CNN.