Fuelled by unusually warm ocean waters in the tropical Pacific, El Niño conditions are developing and are set to influence global temperature and rainfall patterns, increasing the risk of extreme weather over the coming months, according to the World Meteorological Organisation (WMO).

A new WMO El Niño/La Niña Update indicates an 80% likelihood of an El Niño event during June-August 2026. Probabilities for this to continue until at least November are near or above 90%. Although some uncertainty remains about El Niño peak strength and timing, most forecast models suggest it will be at least moderate – and possibly strong.

WMO El Niño/Updates are the world’s most authoritative source of information for governments, humanitarian agencies and climate-sensitive sectors like agriculture, health, energy and water management. They are based on a consensus of models from WMO Global Producing Centres, experts from National Meteorological and Hydrological Services and climate prediction centres around the world and are produced through a collaborative effort between the WMO and the International Research Institute for Climate and Society.

In late April to mid-May, the sea-surface temperature in the central-eastern Equatorial Pacific – the area used as a monitoring reference – was approaching El Niño thresholds, according to observations from different platforms used by WMO.

These increasing surface anomalies are being fed by unusually warm subsurface conditions across the tropical Pacific, with temperatures exceeding 6 °C above average and providing a substantial reservoir of heat that is contributing to the observed surface warming.

Meanwhile, the Southern Oscillation Index – which is the atmospheric component of El Niño – is also consistent with developing El Niño conditions.