El Niño could return in 2026
2026 at risk of heat waves
El Niño, a natural phenomenon that often makes weather around the world more "extreme" and can temporarily add heat to the planet's average temperature, may form again in the Pacific Ocean. The US agency NOAA estimates that the probability of an El Niño in the second half of 2026 (late summer and beyond) is about 50-60 per cent. At the same time, NOAA emphasises: such forecasts in advance remain uncertain, especially during transitional seasons.
What are El Niño and La Niña?
They are two phases of the same natural "switch" in the tropical Pacific Ocean - ENSO. It changes the water temperature and winds over the ocean, and then shifts the usual rainfall and drought patterns in different regions by a chain. The shifts occur irregularly - about once every 2-7 years.
Why it matters now
Even without El Niño, the planet continues to heat up due to the long-term trend of global warming. The World Meteorological Organisation reports that 2025 was among the warmest years on record (2nd or 3rd in different datasets).
And 2024 was confirmed by official services and scientific agencies as the warmest year on record, overtaking the 2023 record.
What weather effects occur during El Niño?
The general picture is that some places are more likely to experience heavy rains and floods, while others are more likely to experience droughts and heat waves. WMO, for example, links El Niño to wetter conditions in the Horn of Africa and southern USA, as well as unusually dry and warm weather in Southeast Asia, Australia and southern Africa.
WHO also notes typical regional shifts, with drier conditions in northern Brazil and heavy rain possible in northern Peru and Ecuador.
What has changed in NOAA's calculations
In February, NOAA/CPC switched to a new metric for tracking ENSO phases, the Relative Oceanic Niño Index (RONI). The reason is simple: the ocean is warming rapidly, and comparisons to the "climate norm" of past decades can lag. The new index looks at how much the Niño-3.4 region is warmer/colder than the rest of the tropics, so that the El Niño and La Niña signal can be more easily separated from overall warming.