El Niño develops, NOAA estimates 63% chance of a very strong event in 2026–27 winter

El Niño conditions have developed in the tropical Pacific Ocean and are expected to strengthen through the Northern Hemisphere winter of 2026-27, according to the National Oceanic and Atmospheric Administration (NOAA). The Climate Prediction Center (CPC) issued an El Niño Advisory on June 11, 2026, after oceanic and atmospheric conditions shifted into an El Niño pattern. Source