The World Meteorological Organization (WMO) has warned that El Niño will continue to strengthen in the coming months, and has indicated that sea surface temperatures in the central and eastern tropical Pacific will reach record levels between October and December 2026. The agency also maintains a probability close to 100% that the phenomenon will persist until February 2027, a development that, according to the agency, could place it among the most intense episodes recorded since at least 1950.
The Secretary-General of the WMO, Celeste Saulo, conveyed this diagnosis during the Global Heat Forum, held in Bangkok (Thailand), where she emphasized that the episode has rapidly consolidated and that its intensification will increase the risk of extreme heat, droughts, and floods in different regions of the planet.
A scientific consensus based on 13 forecasting centers
The WMO's estimate is based on a consensus among 13 national and international centers, with headquarters in cities such as Washington, Tokyo, London, and Pune, and on the real-time exchange of data from oceanic buoys, satellites, and radiosondes, a system coordinated by the organization itself.
According to the institution, the Niño 3.4 index, which measures anomalies in sea surface temperature in the east-central equatorial Pacific, has shown a very notable increase in recent months, rising from an average of +1.6 °C above normal in June 2026 to +2.5 °C in August.
Looking ahead to October, November, and December, the WMO expects the average seasonal anomaly in that region to reach around +3.7 °C, with a peak expected around December. The agency states that this is the highest value since observations began and surpasses the previous record of +2.6 °C, recorded between November 2015 and January 2016.
More surface heat and alterations in rainfall
In its Global Seasonal Climate Update, the WMO indicates that El Niño will continue to intensify before reaching its expected maximum in December and warns that it is likely to generate above-average temperatures in much of the planet, in addition to significantly modifying rainfall patterns.
“It is likely to cause above-average temperatures across much of the planet and alter rainfall patterns, increasing the risk of droughts and floods in different regions,” the organization stated in its monthly report on the global seasonal climate.
The Secretary-General of the WMO, Celeste Saulo, also explained that El Niño does not add new heat to the planet, but rather releases the heat that the ocean had already accumulated below the surface. “(This is the) reason why an intense event usually becomes one of the warmest years on record (as happened in 2024). The ocean from which it draws heat is the warmest we have ever recorded. There is simply more heat available to release,” she noted.
Extreme heat waves due to the seasonal signal
The Global Seasonal Climate Update predicts a very high probability of above-average temperatures (1993-2009) in large areas during the months of October to December, a situation that the WMO considers a “strong seasonal signal” that increases the probability of extreme heat waves and heat-related impacts.
Regions with more rain and areas with widespread drought
The report points to a precipitation signal consistent with an intense El Niño episode, with an increase in above-normal rainfall in the central and eastern equatorial Pacific, east of the international date line.
The WMO also forecasts wetter-than-usual conditions in the Horn of Africa, parts of Central Asia and the East Asian coast, the northern Arabian Peninsula, areas of North America south of 45°N, and southeastern South America.
Conversely, the agency anticipates widespread drought in the western Pacific and the equatorial Atlantic, a band that will extend across the South Pacific to the southern tip of South America. It also forecasts drier-than-normal conditions in the Indian subcontinent, southern Central America, parts of the Caribbean, and northwestern South America.
Other ocean basins and effect on forecasts
The WMO adds that other ocean basins also influence seasonal evolution. In this regard, it expects the positive Indian Ocean Dipole, a climate pattern capable of significantly influencing regional rainfall, to reach its maximum in October and then recede. Between October and December, the expected seasonal anomaly for this indicator will be around +0.5 °C.
Likewise, the Global Seasonal Climate Update forecasts that sea surface temperatures in the equatorial Atlantic basin will remain above normal during the analyzed period.
Preparation and international coordination
The WMO and its members have activated mechanisms to help reduce the impacts of El Niño in different economic sectors, while National Meteorological and Hydrological Services and regional climate outlook forums work periodically with decision-makers to provide updated information.
The agency also recalled that regular updates are being sent to the entire United Nations system and humanitarian partners, with the aim of supporting preparedness and risk management tasks through the WMO Coordination Mechanism.