El Niño is almost certain to make its return this year, and it may stick around through the Northern Hemisphere winter, the National Weather Service (NWS) announced on Thursday.
There’s an 82 percent chance that El Niño will “emerge” between May and July, and it is expected to continue through this winter. There’s a 96 percent chance it will be occurring in December through February 2027. It’s still unclear, however, how long or how strong this El Niño might be.
El Niño is a cyclic climate event that is fueled by ocean temperatures and wind. It can throw off weather patterns and drive up global temperatures, so preparation is key. In 2023 and 2024 the planet saw record-high temperatures in part because of an El Niño event that amplified the effects of climate change.
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Federal forecasters rely on a combination of measurements—sea surface temperatures and changes in wind patterns—to predict when El Niño will come back. To be an official El Niño year, surface temperatures in a section of the Pacific Ocean must rise and stay about 0.5 degree Celsius higher than normal, according to the National Oceanic and Atmospheric Administration, which houses the National Weather Service.
Just two months ago, in March, the United Nations’ World Meteorological Organization estimated that the chances of an El Niño return in May through July were about 40 percent. The most recent forecast shows a much more elevated risk of early arrival.

