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La Niña conditions have once again returned to the waters of the central equatorial Pacific Ocean, meteorologists said on Thursday (October 9). This is the fifth time in six years that the natural weather phenomenon has emerged.
Experts suggest that this La Niña will not be strong and it will not stay for long. “La Niña conditions emerged in September 2025… In summary, La Niña conditions are present and favored to persist through December 2025-February 2026,” the US National Oceanic and Atmospheric Administration (NOAA) said in a statement on Thursday.
Here is a look at La Niña and its impact on India.
La Niña is a phase of what is known as the El Niño Southern Oscillation (ENSO), a climate phenomenon characterised by changes in sea temperatures along the central and eastern tropical Pacific Ocean, accompanied with fluctuations in the atmosphere overhead. ENSO influences, alters, and interferes with global atmospheric circulation, which, in turn, influences the weather worldwide.
ENSO has three phases – warm (El Niño), cool (La Niña), and neutral — which occur in irregular cycles of two to seven years.
In the neutral phase, the eastern side of the Pacific Ocean (near the northwestern coast of South America) is cooler than the western side (near the Philippines and Indonesia). This is due to the prevailing wind systems that move from east to west, sweeping the warmer surface waters towards the Indonesian coast. The relatively cooler waters from below come up to replace the displaced water.
In the El Niño phase, these wind systems weaken, leading to less displacement of warmer waters off the South American coast. Consequently, the eastern Pacific becomes warmer than usual. The opposite happens in the La Niña phase — the trade winds become stronger than usual, and push larger quantities of water to the western Pacific.
In India, El Niño is associated with decreased rainfall and higher temperatures, while La Niña is associated with increased rainfall and hence lower temperatures.
Experts suggest that La Niña may lead to a colder winter in several parts of India, especially in the northern region. It may result in cold waves and increased snowfall in hilly regions.
However, La Niña does not necessarily mean a colder winter. One reason is global warming, which may offset the cooling impact of the weather phenomenon.
For instance, the World Meteorological Organization (WMO) last month said that despite the return of La Niña, global average temperatures would remain above normal.
“Typically, La Niña brings climate impacts that are the opposite of El Niño, especially in tropical regions. However, naturally occurring climate events such as La Niña and El Niño are taking place in the broader context of human-induced climate change, which is increasing global temperatures, exacerbating extreme weather, and impacting seasonal rainfall and temperature patterns,” the WMO said.
