This Indian City Could Face High Flood Risk As Conditions Build For Historic El Niño

Scientists are warning that developing El Niño conditions in the Pacific Ocean could sharply increase the risk of extreme rainfall and flooding in Chennai and parts of southern India later this year.

According to researchers and meteorological experts, a powerful oceanic phenomenon known as a Kelvin Wave is currently moving across the Pacific, strengthening the likelihood of El Niño formation during 2026.

Experts say this could significantly influence India’s weather patterns, especially the northeast monsoon that heavily impacts Chennai and coastal Tamil Nadu between October and December.

What Is Happening In The Pacific?

Scientists have detected unusually warm ocean temperatures spreading eastward across the equatorial Pacific Ocean through a Kelvin Wave — a large subsurface

pulse of warm water that often precedes El Niño events.

El Niño occurs when Pacific Ocean temperatures rise abnormally, disrupting global atmospheric circulation and weather systems.

Meteorologists say the current warming trend suggests the Pacific may transition into a full El Niño phase later this year.

Why Chennai Could Be At Risk

While El Niño is often associated with weaker southwest monsoons in India, it can also intensify the northeast monsoon over Tamil Nadu.

Experts warn that this raises the possibility of heavier rainfall episodes over Chennai and neighbouring districts during the latter half of the year.

Climate scientists noted that past El Niño years have coincided with devastating flood events in Chennai, including the catastrophic 2015 floods.

The city’s geography, rapid urbanisation and drainage challenges make it especially vulnerable to intense rainfall.

Northeast Monsoon Could Turn More Intense

Researchers say warmer sea surface temperatures around the Bay of Bengal combined with altered wind circulation during El Niño conditions can create favourable conditions for stronger rain-bearing systems over southeast India.

This could lead to:

Increased frequency of heavy rain spellsUrban flooding risks in ChennaiStronger cyclonic activity in the Bay of BengalHigher chances of waterlogging and infrastructure disruptionExperts Call For Early Preparedness

Scientists emphasised that El Niño forecasts are still evolving and weather impacts may vary in intensity.

However, they stressed the importance of early planning by civic authorities, disaster management teams and urban planners given Chennai’s history of monsoon flooding.

Officials are expected to closely monitor Pacific Ocean temperatures and monsoon models over the coming months as India heads toward the 2026 northeast monsoon season.