3 September 2026
Geneva, Switzerland (WMO) – El Niño is firmly established and will intensify into a very strong event in the coming months, with big impacts on rainfall and temperature patterns and associated risks of floods, drought and extreme heat, according to a new update from the World Meteorological Organization (WMO).
Key messages
- El Niño is firmly established and is expected to strengthen further
- WMO Forecasts show near 100% likelihood that it will persist through February 2027
- Exceptionally warm tropical Pacific Ocean conditions support further intensification
- A very strong El Niño can significantly shift rainfall and temperature patterns worldwide and fuel extreme weather
- WMO and National Meteorological and Hydrological Services step up preparedness and early-warning efforts for an exceptional event
Exceptional ocean heat in the tropical Pacific
Sea surface temperatures across the central-eastern equatorial Pacific, the region at the heart of El Niño, are already well above average – one of the tell-tale signs of El Niño – and are continuing to rise.
The widely used Niño 3.4 index, which measures sea surface temperature anomalies in central-eastern equatorial Pacific has strengthened markedly from an average +1.5 °C above normal during May-July 2026 and +2.0 °C above normal in July. Weekly values subsequently increased further between late July and mid-August, ranging from approximately +2.2 °C to +2.6 °C above average, indicating continued intensification.
Even more exceptional warmth is present below the ocean surface. In some areas, subsurface ocean temperatures were more than 8°C above average during July and early August.
Together, the surface and subsurface ocean conditions provide strong support for continued El Niño conditions and the potential for further strengthening during the coming months, the Update says.
Confidence in the outlook is high. Strong and mutually reinforcing oceanic and atmospheric signals, together with close agreement among seasonal prediction systems indicate that El Niño will persist at least into early 2027.
Very Strong El Niño does not mean the same impacts everywhere
El Niño and La Niña are among the most powerful naturally occurring influences on the global climate system. A very strong event increases the likelihood of major changes in rainfall, temperatures and atmospheric circulation across many regions of the world.
However, the strength of an El Niño event alone does not determine how severe its impacts will be in any individual country or region.
Its effects vary according to location and season and can be modified by other climate drivers, including conditions in the Indian and Atlantic Oceans.
WMO has therefore issued a complementary Global Seasonal Climate Update, which brings together information about El Niño and other major climate drivers, enabling a more refined picture of expected conditions.
For September–November 2026, WMO multi-model forecasts indicate an increased likelihood of above-normal temperatures across almost all land areas, alongside rainfall patterns showing a pronounced and classic atmospheric response to the strong Pacific El Niño.
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