El Niño is expected to continue to intensify in the coming months and reach a very strong intensity before reaching its peak at the end of 2026, points out a new update from the World Meteorological Organization (WMO), the meteorological and climate arm of the United Nations (UN).
The forecast draws attention mainly due to its level of confidence. The models put together by the agency indicate an almost 100% probability of El Niño remaining both between September and November and between December and February 2027.
For the WMO, neutral conditions have practically no chance during this period, and there is no sign of La Niña returning.
🌊 Understand: El Niño and La Niña are the two phases of the same climate phenomenon, called ENSO (El Niño-Southern Oscillation). El Niño is characterized by warming greater than or equal to 0.5°C of the waters of the equatorial Pacific Ocean.
The scenario is supported by a strong warming of the Pacific Ocean and changes in the atmosphere compatible with an increasingly intense El Niño.
The expectation is that the phenomenon will continue to influence temperatures and rainfall in different regions of the planet during spring and summer in the Southern Hemisphere.
⚠️ Still, the WMO makes an important caveat: the intensity of El Niño, alone, does not allow us to predict the size of the impacts in a given city, country or region.
Other factors, such as conditions in the Atlantic and Indian Oceans, can also reinforce or weaken their effects.
In the coming months, for example, the organization also predicts the development of a positive phase of the Indian Ocean Dipole, in addition to the maintenance of warmer than normal waters in the Equatorial Atlantic, patterns that could modify the typical response to El Niño.
Therefore, even regions that historically receive more or less rain during strong episodes can show considerable differences from one event to another.
“We are already seeing disruption and devastation caused by droughts and floods, and we expect these impacts to increase as El Niño intensifies,” said Celeste Saulo, WMO Secretary-General.
Image from August 3, 2026, made with data from the Sentinel-6 Michael Freilich satellite, shows changes in the level of the Pacific Ocean associated with El Niño. — Photo: Sentinel-6 Michael Freilich/NASA/NOAA
🌊 Pacific is warming quickly
One of the main signs of strengthening is in the so-called Niño 3.4 region, a band of the Equatorial Pacific used by scientists to monitor the evolution of El Niño.
In May, sea surface temperatures in this area were about 0.9°C above average. In July, the difference had already reached 2°C.
After that, weekly measurements between late July and mid-August showed values approximately 2.2°C to 2.6°C above normal, indicating that warming continued to increase.
➡️ And the heat is not restricted to the surface. According to the WMO, in some areas of the Pacific, water below the surface was more than 8°C above average in July and early August.
This reservoir of exceptionally warm water is yet another factor that favors the maintenance and strengthening of El Niño in the coming months.
EVERYTHING YOU NEED TO KNOW ABOUT EL NIÑO:
Climate models gathered by the organization now indicate that the average anomaly in the Niño 3.4 region could reach approximately 3.6°C between September and November, with strengthening reaching a maximum between November and December.
The projection for November, alone, reaches 3.9°C above average, although this value is an estimate from the models and has a margin of uncertainty.
📝 UNDERSTAND: an anomaly of 3.6°C does not mean that the entire Pacific Ocean will be 3.6°C warmer nor that the air temperature will increase by the same amount. The number represents how much the sea surface temperature in a specific region of the Pacific can be above its historical average.
🌡️ More heat in much of the planet
In addition to the specific update on El Niño, the WMO released a climate projection for the period from September to November 2026.
Models indicate an increased likelihood of above-normal temperatures across nearly all major continental areas, with particularly consistent signals across parts of Africa, South America, Australia and Asia.
In South America, the heat signal is strongest mainly between the Equator and 30° south latitude, a range that covers a significant portion of the continent. Further south, the forecast becomes less uniform.
Rainfall must follow a very different distribution from one region to another.
On the South American continent, the models show a greater probability of below-average volumes in the northwest and throughout northern areas, while at the same time indicating a band with a greater chance of above-normal rain in the southeast of South America.
This is compatible with one of the best-known characteristics of El Niño: the phenomenon alters the circulation of the atmosphere and can displace rain corridors, making one region wetter at the same time that another faces drier conditions.
🌎 What El Niño is — and why it matters so much
El Niño is an unusual warming of the waters of the Pacific Ocean near the Equator.
It is part of a natural climate cycle that alternates hot (El Niño), cold (La Niña) and neutral phases — with impacts in various regions of the planet.
This warming changes the circulation of the atmosphere and alters the pattern of rainfall and temperatures in different parts of the world.
In Brazil, the effects tend to be uneven: the South tends to have more rain, while areas of the North and Northeast may experience drier periods.
The phenomenon also influences global temperature. In years of more intense El Niño, the planet tends to experience above-average heat, adding to global warming.
The intensity varies from one event to another, as do the impacts. And, with the planet already hotter, even moderate episodes can have stronger effects than in the past.
Aerial view of a burned area in the Amazon, near Apuí, in Amazonas, on August 11, 2020. — Photo: Ueslei Marcelino/Reuters
🌧️ Possible impacts in Brazil
Historically, El Niño changes the rainfall and temperature pattern in the country and causes:
increased rainfall in the South, with a greater risk of extreme events;
reduction of rainfall in the North and parts of the Northeast;
more irregularity in precipitation in the Southeast and Center-West;
higher frequency of hot flashes.
According to experts, one of the main expected effects is the increase in prolonged periods of heat, especially in spring and summer.
El Niño and La Niña — Photo: Arte g1/Luisa Rivas
