El Niño Warning: Why the Emerging Climate Pattern Could Bring Extreme Weather Across Asia

The World Meteorological Organization (WMO) states that the current strengthening El Niño is likely to become stronger by the end of 2026, raising the chances of extreme heat and major changes in rainfall patterns in parts of Asia and in other areas.

In its recent update on Sept. 3, the agency indicated that there is almost a 100% probability of El Niño continuing until February 2027 and that the phenomenon could develop into a very strong one before reaching its peak at the end of the year.

The recent forecast represents an even greater escalation than the one issued by the WMO on July 31, when it had stated that El Niño was expected to intensify between August and October. The multi-model forecasts had predicted that seasonal-average sea-surface temperature anomalies would exceed 2.9°C in the main monitoring areas.

El Niño is a natural climate pattern characterised by abnormally high sea-surface temperatures in the central and eastern parts of the equatorial Pacific; it modifies atmospheric circulation and is capable of causing changes to rainfall and temperature patterns far beyond the Pacific, although the extent of these effects varies depending on location, season and the interaction with other climate factors.

Asia Faces Drought, Heat and Rainfall Shifts

In parts of South and Southeast Asia, El Niño is linked to a greater chance of below-normal rainfall. The WMO’s assessment for July noted drier conditions in certain areas of South Asia, Indonesia and Southeast Asia, and FEWS NET’s regional forecast for 2026-27 also cites below-average rainfall and extreme heat as the main concerns for South and Southeast Asia.

On Aug. 21, the ASEAN Specialised Meteorological Centre (ASMC) stated that El Niño conditions had been established, the Niño3.4 index having intensified in July and at the beginning of August. The ASMC added that El Niño conditions were expected to persist throughout the second half of 2026 and into early 2027, with a forecast indicating that they would strengthen between October and November.

The monitoring carried out by ASMC showed that the Niño3.4 index had reached the El Niño threshold in June 2026 and became stronger in July. The centre warned that the regional effects will depend on how El Niño interacts with other climate factors.

The Asia outlook from FEWS NET states that the below-average monsoon rainfall linked to El Niño might limit agricultural production in certain areas of the region, even though the effects differ from country to country.

Indian Ocean Dipole Adds Another Climate Signal

El Niño is developing alongside another ocean-atmosphere pattern, called the Indian Ocean Dipole (IOD).

A positive IOD occurs when sea-surface temperatures are relatively warmer in the western Indian Ocean and cooler in the eastern Indian Ocean. WMO says a positive IOD is expected to develop and could modify the typical effects of El Niño across the Indian Ocean basin.

ASMC said the IOD was neutral in July but that models indicated a positive phase was likely between August and December 2026.

The development of El Niño and a positive IOD doesn’t mean every country will experience the same conditions. WMO stresses that the strength of El Niño alone does not determine the severity of impacts in an individual country or region. Local conditions, seasonal timing and other climate drivers can strengthen, weaken or alter the expected effects.

El Niño Adds Pressure to Global Temperatures

WMO’s September outlook projects an increased likelihood of above-normal temperatures across almost all land areas for September-November 2026. The agency said the strongest signals extend across many densely populated regions, including the Indian subcontinent and eastern Asia.

WMO scientist Alvaro Silva had flagged the temperature risk in July. “El Niño will also give an extra boost to global temperatures,” Silva said. “We know that during El Niño years, the global temperatures normally reach record levels.”

The statement came as WMO warned in July that El Niño’s influence could extend beyond 2026 and into 2027. The agency said the phenomenon can increase the likelihood of extreme weather and climate events in different parts of the world, on top of longer-term human-induced climate change.

WMO Secretary-General Celeste Saulo called the current forecast a critical window for governments. “El Niño is one of the most closely monitored climate phenomena in the world. But forecasts in themselves do not prevent hazards; people do,” Saulo said in the July 31 statement. “The decisions we make today will shape the impacts we experience tomorrow.”

UN Secretary-General António Guterres framed the intensification in starker terms. “El Niño is not just on our doorstep; it is inside the house and turning up the heat,” Guterres said. “El Niño is strengthening, adding fuel to a planet already on fire with scorching heat domes, apocalyptic wildfires and record hot seas.”

Pacific Warming Builds Toward Year-End Peak

WMO’s outlook has strengthened since the beginning of 2026. In March, the agency said El Niño chances were rising as La Niña conditions faded. By April, forecasts pointed to a possible El Niño during the middle of the year.

On June 2, WMO said El Niño conditions were developing and could influence global temperature and rainfall patterns. By July 3, the agency said a strong El Niño was expected to develop rapidly during July-September.

On July 31, WMO said the event was continuing to intensify and was expected to dominate global climate patterns during August-October. Its Sept. 3 update went further, saying El Niño was firmly established and expected to intensify into a very strong event before peaking toward the end of 2026.

WMO’s latest Niño3.4 observations show the scale of the warming. The index averaged about 1.5°C above normal during May-July 2026 and reached about 2.0°C above normal in July. Weekly values rose further to roughly 2.2°C-2.6°C above average between late July and mid-August, according to the agency.

Weather Impacts Could Continue Into 2027

The September update from the WMO states that there is nearly a 100% chance that El Niño will last until February 2027; the agency anticipates that the event will become stronger in the coming months and will reach its peak toward the end of 2026.

The forecast doesn’t indicate that all regions will have severe weather, and the WMO states that national meteorological and hydrological services are still the reliable source of warnings and information relevant at the country level.

The WMO states that its regional centers and the national meteorological services are working on converting the seasonal forecasts into information which can aid decisions in the areas of agriculture, water, energy, health and disaster management.