The India Meteorological Department (IMD) confirmed on Wednesday that the southwest monsoon has advanced into additional parts of the Arabian Sea, Lakshadweep area and Bay of Bengal despite missing its expected onset date. According to reports from PTI, the monsoon has further progressed beyond the initial forecast areas, indicating continued favorable conditions for seasonal advancement. The IMD had earlier estimated that the monsoon would arrive in Kerala on May 26 with a model error of +/- four days, but the actual onset was delayed. This year's delayed arrival is part of normal seasonal variability, as the monsoon usually sets over Kerala around June 1, marking the beginning of the monsoon season (June to September) in the country.
The IMD has now issued revised forecasts predicting lower than average seasonal rainfall, with an expected total of 80 cm compared to the long-term average of 87 cm, as reported by PTI. This reduction is partly attributed to potential El Niño conditions, known to cause diminished rainfall. In its monthly forecast on May 1, the department had said that El Niño-Southern Oscillation (ENSO)-neutral conditions over the equatorial Pacific were evolving toward El Niño conditions. The last time El Niño conditions developed was in 2023, with these conditions emerging previously in 2002, 2009, and 2015. While most regions anticipate below-normal precipitation, certain areas in the Northeast, Northwest, and South Peninsular India may experience normal to above-normal rainfall levels, adding complexity to the forecast.
According to the IMD statement reported by PTI, conditions are favorable for further advance of southwest monsoon into some more parts of southwest and southeast Arabian Sea, Lakshadweep area, southwest, eastcentral and westcentral Bay of Bengal, remaining parts of southeast Bay of Bengal and some parts of northeast Bay of Bengal during the next 2-3 days. This expansion represents the monsoon's continued progression across the Indian subcontinent. The monsoon's usual onset timing makes this year's delayed arrival significant, as last year, the onset of monsoon happened on May 24, making this year's delayed arrival part of normal seasonal variability.
As reported by PTI, India receives more than 70 per cent of its annual rainfall during the monsoon months, making the season critical for agriculture, drinking water supply, hydroelectric power generation and groundwater replenishment. The monsoon season is essential for the country's agricultural economy and water resources. Below normal seasonal rainfall is expected over most parts of the country, except some areas over Northeast, Northwest, and South Peninsular India, where normal to above normal rainfall can take place. The IMD's revised forecast indicates that this year, the southwest monsoon seasonal rainfall over the country is expected to be below normal, with the department's April forecast confirming this assessment.
