Imd Alert El Nino Pacific Ocean India Monsoon Deficit

The El Niño has developed in the Pacific Ocean, the India Meteorological Department (IMD) declared on Friday. " El Niño is expected to strengthen further during the southwest monsoon season," the IMD said in its El Niño Southern Osciallation (ENSO) bulletin. This announcement came a day after the emergence of El Niño was made public by the US-based National Oceanic and Atmospheric Administration (NOAA) which had further noted, " El Niño would peak during the November – January period." NOAA has predicted the current El Niño strength to reach its peak and touch the ‘very strong’ category during November – January, 2027. ‘Very strong’ El Niño is categorised when the sea surface temperature along the Nino 3.4 region (the main region for denoti ng ENSO phase) surpasses 2 degrees Celsius. El Niño Southern Oscillation (ENSO) is a naturally occurring ocean-atmospheric phenomenon observed along the central and equatorial Pacific Ocean. It has three phases - warm (El Niño), neutral and La Nina (cool). El Niño means ‘little boy’ and La Nina means ‘little’ girl in Spanish. The ENSO phase is decided by the sea surface measured temperatures along the equatorial Pacific Ocean. ENSO phases can emerge once in 2 to 7 years, with varying intensities and alternating phases. When the temperature in one of the regions along the equatorial Pacific Ocean region, known as a Niño 3.4 region, surpasses 0.50 degrees Celsius, an El Niño is declared. “El Niño developed over the past month (May), as confirmed by the above-average sea surface temperatures across the central to eastern equatorial Pacific Ocean. The latest weekly Niño 3.4 index value was +0.7 degree Celsius,” NOAA said. The temperatures along other regions of the equatorial Pacific Ocean measured +0.7 degree Celsius (the westernmost region / Niño 4 region) and +2.1 degrees Celsius along the easternmost region (Niño 1+2 region). IMD, similarly, noted a surge in the sea surface temperatures along the both the Bay of Bengal and the Arabian Sea during May. " In comparsion to sea surface temperatures recorded in April, positive (above normal) temperatures were predominantly evident along the eastern Indian Ocean, northern Arabian Sea and northern Bay of Bengal during May," IMD said. Like El Niño in the Pacific Ocean, India is also affected by its Indian Ocean counterpart, known as the Indian Ocean Dipole (IOD). This, too, has three phases : positive, neutral and negative. The IMD said that during the southwest monsoon season, IOD would continue to remain in the neutral phase. This phase commenced in early 2026 and is expected to remain so for most part of the year. Since an episode of El Niño can last anywhere between a few months to upto two years, the peak of El Niño generally coincides with the winter season along the northern hemisphere. El Niño and monsoon: Over India, many El Niño years in the past have seen subdued monsoon rainfall and extreme temperatures. This year, the India Meteorological Department (IMD) has forecast below-average rainfall during the ongoing southwest monsoon season mainly due to El Niño. The country-wide seasonal rainfall is expected to be 10 per cent short of normal. Except northeastern India, all other geographical regions of the country will receive below normal rainfall during June – September this year. Climatologically, during El Niño years, northeast and extreme southern India receive normal rainfall while the rest of the country suffers below-normal rain. Due to subdued rainfall, the monsoon season may also see a spike in temperatures.