El Niño is forecast to return as early as May, which could bring above-normal temperatures to almost everywhere on Earth, according to a new report.

El Niño events occur every two to seven years as part of the El Niño-Southern Oscillation (ENSO) natural climate cycle in the Pacific Ocean. The ENSO cycle flips between the warmer El Niño phase and the cooler La Niña phase, with neutral periods in between. El Niño periods bring elevated sea surface temperatures in the central and eastern Pacific, thereby weakening or reversing trade winds and strongly disrupting global temperatures and rainfall patterns.

In a Global Seasonal Climate Update published April 21, the World Meteorological Organization (WMO) reported that El Niño is set to develop during the May to July season. Although the confidence of the prediction will improve after April, models currently suggest this El Niño could be a "strong event," according to the WMO.

"After a period of neutral conditions at the start of the year, climate models are now strongly aligned, and there is high confidence in the onset of El Niño, followed by further intensification in the months that follow," said Wilfran Moufouma Okia, chief of climate prediction at the WMO.

The impacts of El Niño periods on global agriculture are profound, with studies linking the events to famine in Europe; civil wars in tropical regions; and droughts, floods and forest fires around the world.

The most recent El Niño period lasted from May 2023 to March 2024 and contributed to 2024 being the hottest year on record.

Now, the Global Seasonal Climate Update predicts a "rapid warming trend" for May, June and July. Elevated temperatures are highly likely in southern North America, Central America, the Caribbean, Europe and Northern Africa.

Rainfall patterns will shift greatly across the world. Some parts of North America could get wetter, but the lack of a clear signal means it's currently unknown.

In March, the National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center announced that there was a 62% chance of El Niño emerging between June and August. NOAA has since said there's a 61% of El Niño returning in May to July and continuing through the rest of the year. The WMO does not use the term "super El Niño," but NOAA predicts a 25% chance of a "very strong" El Niño beginning in November.

The WMO will publish a revised El Niño update in late May.

Sophie is a U.K.-based staff writer at Live Science. She covers a wide range of topics, having previously reported on research spanning from bonobo communication to the first water in the universe. Her work has also appeared in outlets including New Scientist, The Observer and BBC Wildlife, and she was shortlisted for the Association of British Science Writers' 2025 "Newcomer of the Year" award for her freelance work at New Scientist. Before becoming a science journalist, she completed a doctorate in evolutionary anthropology from the University of Oxford, where she spent four years looking at why some chimps are better at using tools than others.