El Niño signals for 2026 raise risk of brushing the 1.5°C threshold

Weather analysts are detecting early signs that El Niño may return in the equatorial Pacific, with a clearer signal expected in the second half of 2026 and potentially lasting into the Northern Hemisphere winter of 2026–2027. 

Such a development could amplify the current warming trend and increase the risk of heatwaves, drought and wildfires in many regions worldwide.

The equatorial Pacific is showing initial indications of a possible shift back towards El Niño conditions, which could emerge in the latter half of 2026 and peak during the Northern Hemisphere winter, according to climate analysts. 

Scientists warn that a renewed El Niño could further reinforce the upward trend in global temperatures.

Severe Weather Europe, a European weather and climate analysis platform, said its latest projections suggest El Niño will return in 2026, intensify in the second half of the year and persist through the 2026–2027 season.

This could mean another year in which global temperatures remain close to—or briefly reach—the 1.5°C warming threshold above pre-industrial levels, alongside heightened risks of heatwaves, drought, wildfires and other climate-related impacts that are worsening at both global and regional levels.

El Niño is the warm phase of the El Niño–Southern Oscillation (ENSO), a natural climate cycle. During El Niño, the global average temperature is often higher than normal. The phenomenon disrupts rainfall patterns worldwide, bringing heavier rain to some regions while leaving others much drier.

In India, several past monsoon-season droughts have been linked to El Niño conditions in the equatorial Pacific.

At present, a weak La Niña—the cooler-than-normal phase of ENSO—still persists in the equatorial Pacific. La Niña peaked in November and is expected to weaken further during the Northern Hemisphere winter.

More recently, however, ENSO temperature anomalies have begun to rise again, signalling that La Niña may be approaching its end.

Severe Weather Europe said the warming in the equatorial Pacific appears to be starting in the west, as shown clearly by sea-surface temperature anomaly data.

Signs of a possible El Niño are becoming even clearer below the ocean surface. Subsurface temperature anomalies show a large pool of warm water in the western Pacific at a depth of about 100–250 metres (300–800 feet).

Severe Weather Europe said this is one reason La Niña is weakening from the west, as these warm-water anomalies continue to expand beneath the surface.

Seasonal forecasts are also pointing towards a transition to El Niño. “The clearest signal of the upcoming El Niño can be seen in the latest seasonal forecast models for the ENSO region,” the platform said. 

ECMWF projections indicate conditions will shift into El Niño during the summer of 2026 and extend into winter. For now, the event is assessed as moderate, though El Niño episodes often prove stronger than early forecasts suggest.

Current signals from sea-surface temperatures, subsurface ocean heat and forecast models resemble conditions observed ahead of the most recent El Niño in 2023–2024, a period associated with record-breaking monthly and annual global temperatures. 

That episode was among the factors that made 2024 the hottest year on record and the first year in which the global average temperature rose above the 1.5°C threshold.