The World Meteorological Organization warns a rapidly intensifying Super El Niño, already hotter than the 1997-98 event, will combine with a positive Indian Ocean Dipole between August and October.
Record sea-surface anomalies above 2.9°C could drive extreme heat, droughts, floods and wildfire risks worldwide, while India’s monsoon may see mixed impacts as IOD partly offsets El Niño’s rainfall suppression.
The El Niño event in the Equatorial Pacific Ocean is already hotter than the peak temperature (in the Niño 3.4 region used for measuring the strength of El Niño) of the 1997-98 Super El Niño event with sea surface temperatures forecast to be the highest in at least the previous 150 years. The World Meteorological Organization (WMO) has already warned of impacts from the steadily intensifying El Niño in the form of above normal temperatures and shifts in rainfall patterns between August and October.
“The rise in Niño 3.4 region sea surface temperatures over the past few weeks has been nothing short of astonishing. We are now hotter than any days during the 1997/1998 Super El Niño event, and we are still many months from the peak.”Zeke Hausfather, climate scientist at Berkeley Earth on social media platform X.
El Niño is the warmer than normal phase of the El Niño Southern Oscillation phenomenon, mainly in the eastern and central Equatorial Pacific Ocean. During such warming of sea surface and sub surface in the region, trade winds above become weaker than normal or sometimes even reverse in direction.
This generally leads to build up of heat and increase in rainfall over the Pacific Ocean and decrease in rainfall over many other regions including over India during the southwest monsoon season. El Niño also generally leads to increase in the global average temperatures and occurrence of heat waves, droughts, wildfires over land and marine heat waves, coral bleaching and other extreme events in the oceans.
The El Niño event of 2026 was declared by the National Oceanic and Atmospheric Administration (NOAA) of the United States on June 11 and has since been strengthening rapidly, according to many observers.
“A Super El Niño event is currently in rapid development. The available forecast data shows this event peaking as one of the strongest such events in recorded history,” wrote meteorologist Andrej Flis on weather platform Severe Weather Europe.
“Combined with exceptionally warm global oceans and the likelihood of a positive Indian Ocean Dipole, the developing El Niño is expected to shape weather patterns across many parts of the world in the months ahead,” said the WMO is a press release on July 31. The WMO expects the El Niño event to become a strong event between August and October. “Multi-model ensemble forecasts from leading global producing centres indicate seasonal-average sea-surface temperature anomalies are expected to exceed 2.9°C in key monitoring regions,” according to WMO.
The peak anomalies are 4-5°C above the normal in August itself, according to Flis which is significant as the peak of El Niño events usually occurs between November and February. Weather models from the US and Europe both predict anomalies in the Nino 3.4 region to cross 2°C significantly and could even cross 3°C making it the strongest event since the El Niño event of 1876-78 which killed millions of people around the world due to widespread famines.
Flis also contends that the real engine of the Super El Niño event is in the warming of waters beneath the surface in the Equatorial Pacific Ocean, especially in the top 500 metres. “This reveals the deep core of this Super El Niño event: a strong, warm anomaly that is now peaking over 8 degrees above normal,” wrote Flis.
Another major ocean atmosphere event that is going to impact temperatures and rainfall patterns around the world is the Indian Ocean Dipole (IOD). During the positive phase of the IOD event, which is developing in the Indian Ocean region, the western parts of the Indian Ocean are warmer than normal while the eastern parts are cooler than normal.
This increases the rainfall over the western Indian Ocean and decreases rainfall over the eastern part. A positive IOD also aids in rainfall over India during the southwest monsoon season which can counteract the suppression of rainfall due to the El Niño. “Together, these oceanic drivers can amplify regional climate impacts including drought, floods and wildfire risk, particularly around the Indian Ocean basin,” according to WMO.
Flis has also analysed that the weather around the world going into winter will be driven by both Super El Niño and the IOD. “With strong rising air in both the central Pacific and Indian Ocean, they launch atmospheric wave trains that directly alter the jet stream across the United States and Canada heading into winter,” wrote Flis. “At the same time, dry sinking air is anchored over Indonesia, locking this atmospheric engine into place. This powerful tropical setup reshapes jet stream behavior on a global scale, shifting storm tracks far beyond North America, also driving broad hemispheric impacts throughout the winter season,” he added.
“El Niño is one of the most closely monitored climate phenomena in the world. But forecasts in themselves do not prevent hazards, people do,” said WMO secretary general Celeste Saulo in a press statement. “This El Niño developing against the backdrop of unprecedented ocean heat and rising temperatures, provides governments and communities with a window of opportunity to anticipate risks and act before impacts unfold. The decisions we make today will shape the impacts we experience tomorrow,” she added.