WMO: Prepare for El Niño

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.

The world must treat it as the urgent climate warning it is. El Niño conditions will pour fuel on the fire of a warming world. Impacts will hit even harder, travel even farther, and cross borders with devastating speed. The only effective response is climate action equal to the crisis – ending the addiction to fossil fuels, accelerating the shift to renewables, protecting the most vulnerable, and delivering early warning systems for all.

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.

Monitoring informs 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.

It generally begins developing between March and June and reaches its peak intensity between November and February, with impacts on global temperatures typically being most pronounced in the second year after development.

The effects of each El Niño/La Niña event vary depending on the intensity, duration, time of year when it develops, and also how it interacts with other climate variability modes (such as the Indian Ocean Dipole). Not all regions of the world are affected, and even within a region, impacts can be different. Even when ENSO is neutral, extreme weather can still occur.

The strength of an ENSO event is highly significant – whether it is classed as weak, moderate, strong or very strong. Even a moderate El Niño makes some weather and climate extremes more likely.

WMO does not use the term “super El Niño” because it is not part of standardized operational classifications.

There is no evidence that climate change increases the frequency or intensity of El Nino events. But it can amplify associated impacts because a warmer ocean and atmosphere increases the availability of energy and moisture for extreme weather events such as heatwaves and heavy rainfall.

Typical impacts

Each El Niño event is unique in terms of its evolution, spatial pattern and impacts.

However, it is typically associated with increased rainfall in parts of southern South America, the southern United States, parts of the Horn of Africa and central Asia, and drier conditions over Central America, northern South America, the Caribbean, Australia, Indonesia, and parts of southern Asia.

During the Boreal summer, El Niño’s warm water can fuel hurricanes in the central/eastern Pacific Ocean, while it hinders hurricane formation in the Atlantic Basin. Thus, the US National Oceanic and Atmospheric Administration (NOAA) is forecasting a below-normal hurricane season for the Atlantic basin this year.

The Greater Horn of Africa Climate Outlook Forum (GHACOF) predicts a high likelihood of below-normal rainfall across much of the northern Greater Horn of Africa during the critical June–September rainy season.

Similarly, South Asia is expected to receive below average monsoon rainfall, according to the South Asian Climate Outlook Forum.

The Central America region expects drier and warmer conditions according to the Central America Climate Outlook Forum.