The southwest monsoon season (June-September) officially ended on Wednesday after delivering one of the weakest rainfalls in over a decade. The country received 759 millimetres (MM) of rainfall against the benchmark—the long period average of 868 mm based on average precipitation during the 1971-2020 period, according to the India Meteorological Department (IMD).
Withdrawal of the annual phenomenon, which accounts for over 70% of the country’s annual rainfall, is currently underway; total withdrawal may occur in a fortnight.
According to the IMD, rainfall during the monsoon season from June 1 to September 30 was 12.6% below the long-period average (LPA), placing it in the “deficient” category. The shortfall was the worst since 2015, when precipitation was 12.7% below the benchmark.
“Despite the impact of El Nino, there were 77 low pressure system days during the 2026 monsoon season, which is higher than the normal of 57 day,” Mrutyunjay Mohapatra, Director General of Meteorology, IMD said in a briefing.
Previously, overall monsoon rainfall was in the “deficient” range in 2002 (-20.9%), 2009 (-18.3%), 2015 (-12.7%) and 2014 (-10.15%).
Regionally, central India received rainfall in the normal range, while northwest India (-5.8%), east and northeast India (-25.6%) and south peninsular India (-24.4%) recorded below-normal precipitation.
Out of the 36 meteorological subdivisions, eighteen subdivisions, or 53% of the area, received normal rainfall, while 17 subdivisions, or 42%, recorded deficient rainfall during the season, the met department said.
After scanty rainfall in June, when precipitation was 36% below the LPA, monsoon rains revived in July, with rainfall 1% above the LPA. August and September saw a rainfall deficiency of 14% and 8% against the benchmark.
The weather department forecast the northeast monsoon (October-December) to be normal in the range of 88-112% of the benchmark.
In May, the IMD revised its June-September rainfall projection to 90% of the LPA, down from 92% in its April forecast, placing the season in the “below-normal” category.
The IMD classifies ‘normal’ rainfall between 96% and 104% of LPA. Rainfall between 90%-95% is considered ‘below normal’ while precipitation below 90% of LPA is termed ‘deficient’. Rainfall in the range of 105-110% is considered ‘above normal”.