India Records Lowest Southwest Monsoon Rainfall in a Decade Amid El Niño Impact
India's four-month southwest monsoon officially concluded with a national rainfall deficit of 12.6 percent, marking the lowest seasonal precipitation recorded since 2015. According to data released by the India Meteorological Department on Wednesday, the country accumulated 759.4 millimeters of rainfall against a long-period average of 868.6 millimeters.
The subdued performance of the June-September season was driven heavily by the developing El Niño weather pattern in the equatorial Pacific Ocean. Regional distribution showed extreme variance across the subcontinent, with eastern and northeastern subdivisions enduring their driest monsoon season since systematic records began in 1901.
Regional Disparities and Sectoral Pressures
The eastern and northeast region experienced a sharp 25.6 percent deficit compared to normal levels, continuing a multi-year diminishing trend identified by meteorological officials. Meanwhile, the southern peninsula recorded a 24.3 percent shortfall, registering 542 millimeters of precipitation, which stands as the fourth-lowest accumulation in the region since 1901.
At the state level, Keralam recorded a 28 percent rainfall deficit, receiving 1,446.5 millimeters against its normal average of 2,018.6 millimeters. This performance marked the seventh-lowest southwest monsoon season for the state since 1901 and the fourth-lowest since 2001, leaving approximately 70 percent of its districts significantly rain-deficient.
Reservoir Stress in Key Watersheds
Critical hydroelectric basins faced severe depletion as the uneven monsoon cycle played out. Idukki and Wayanad districts in Keralam, which house major water storage facilities and support significant hydropower generation capacity, each received roughly 50 percent less rainfall than normal.
Nationwide, 17 of 36 meteorological subdivisions covering 42 percent of the country's land area were classified as deficient. Punjab, Arunachal Pradesh, and the Assam and Meghalaya subdivisions recorded deficits across all four individual months from June through September.
According to The Hindu, for IMD District Monsoon Assessment, Out of 741 districts assessed nationwide by the IMD, 282 districts were classified as rain-deficient and 34 were classified as 'large deficient'.
Monthly Progression and Dry Spells
The season was characterized by erratic temporal distribution rather than steady precipitation. June recorded a steep 35 percent shortfall, followed by a slight recovery in July driven by a depression over central India that delivered 33 percent more rain than normal for that month.
August and September saw renewed deficits of 16.3 percent and 7.6 percent respectively. IMD Director General M. Mohapatra noted that while initial seasonal projections aligned closely with reality, monthly and regional deviations required ongoing monitoring.
Outlook for October and Winter Crops
As the southwest monsoon begins its withdrawal phase, the weather office anticipates that October will bring hotter and drier conditions than usual across most parts of the country, with overall rainfall likely remaining below 85 percent of the long-period average.
According to The Hindu, for Southern Farmers' Associations, Agricultural stakeholder groups across southern districts demanded formal drought declarations and compensation to cope with crop failures caused by severe peninsular rainfall shortfalls. According to The Hindu, iMD's post-monsoon outlook forecasts October rainfall to remain below 85% of the 75.4 mm normal across most regions, with elevated maximum and minimum temperatures persisting nationwide.
However, meteorological officials indicated that an anticipated increase in western disturbances during El Niño years could improve moisture conditions in northern agricultural belts, aiding soil profiles for upcoming winter sowing cycles.