El Niño is firmly established and will intensify into a very strong event in the coming months, with major 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).
Forecasts from WMO's Global Producing Centres indicate an "exceptionally high likelihood of nearly 100%" that El Niño will persist through to February 2027. This is the first time a WMO El Niño/La Niña Update has been so unequivocal, reflecting the strong agreement within WMO's extensive network of forecasting centers.
Fueled by exceptionally warm ocean conditions across the tropical Pacific, El Niño is expected to strengthen further during the coming months to a very strong intensity before peaking toward the end of this year, with climate impacts continuing well into 2027.
"El Niño is being supersized before our eyes. The science leaves no room for doubt: the planet is in uncharted waters, and those waters are heating up. Sea surface temperatures are rising, temperatures keep climbing, and the world is in the danger zone of extreme weather. The race now is between rising risks and our commitment to take climate action and protect people. We must win that race," said UN Secretary-General António Guterres.
"El Niño in Spanish means boy child – but it has the potential to deliver a massive blow to communities and economies across the world. We are already seeing disruption and devastation from droughts and floods and we expect these impacts to increase as El Niño intensifies," said WMO Secretary-General Celeste Saulo.
"This exceptional El Niño demands exceptional preparation and response. Never before in the 50-year history of the World Meteorological Organization have we launched such a major mobilization with National Meteorological and Hydrological Services who are on the frontline of delivering the forecasts and services to save lives and livelihoods," she said.
"WMO is committed to working closely with partners across the United Nations and humanitarian system to provide the climate intelligence and insights needed to support disaster management and climate-sensitive sectors like agriculture, health, energy and water resources," she said. "We have no time to lose."
WMO El Niño/La Niña Updates are the world's most authoritative source of information for governments and decision-makers. These seasonal forecasts are based on a consensus of models from WMO Global Producing Centres, experts from National Meteorological and Hydrological Services, and climate prediction centers around the world.
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 the central-eastern equatorial Pacific, strengthened markedly from an average of +1.5°C above normal during May–July 2026 to +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.
A 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 — 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 to enable 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.
A positive phase of the Indian Ocean Dipole (IOD) is also expected to develop, reaching a September–October–November 2026 seasonal mean value of 0.9°C. Meanwhile, the equatorial Atlantic basin is forecast to remain generally warm, with sea surface temperatures in both the North and South Tropical Atlantic staying above normal. These conditions may reinforce, weaken, or alter typical El Niño impacts in different regions.
More detailed and locally applicable information is provided through WMO Regional Climate Centres, WMO Regional Climate Outlook Forums, and National Meteorological and Hydrological Services.
Turning Forecasts Into Early Action
El Niño and La Niña are opposite phases of the El Niño–Southern Oscillation (ENSO), one of the most powerful naturally occurring climate patterns on Earth. El Niño is characterized by a warming of ocean surface temperatures in the central and eastern equatorial Pacific. It typically occurs every two to seven years and lasts around nine to twelve months.
El Niño generally begins developing between March and June and reaches its peak intensity between November and February. Its impact on global temperatures can extend beyond the period of peak ocean warming and be most pronounced in the year after development.
Because El Niño can reshape weather and climate patterns thousands of kilometers away from the tropical Pacific, reliable forecasts provide governments, humanitarian agencies, businesses, and communities with valuable time to prepare. WMO members and partners will continue to closely monitor the evolution of the event and regularly update forecasts of its likely regional impacts. National Meteorological and Hydrological Services remain the authoritative source of official warnings and locally relevant climate information.
El Niño is a natural climate phenomenon and is not caused by climate change.
Source: World Meteorological Organization (WMO)