IMD Warns of Below-Normal September Rain as August Deficit Crosses 16%

India's monsoon season is set to close on a weak note, with the India Meteorological Department (IMD) projecting below-normal rainfall for September. The announcement comes after the country recorded a rainfall deficit of over 16% for August, despite several intense spells during the month.

According to the IMD, the seasonal rainfall between June and September is now likely to remain below 90% of the long-period average (LPA). As of the end of August, the cumulative seasonal rainfall stood at 84% of normal. August, which typically accounts for 29% of the season's total rainfall, failed to deliver expected precipitation.

IMD Director General Mrutyunjay Mohapatra attributed the shortfall to the persisting El Nino conditions in the equatorial Pacific Ocean, which have begun to influence the Indian monsoon. The August deficit was the seventh largest for the month since 2001.

While four low-pressure systems developed during August and collectively lasted 26 days, their impact was largely confined to the Indo-Gangetic Plains. The southern peninsula bore the brunt with a deficit exceeding 27%, while central India and the eastern and northeastern regions each saw a shortfall of about 16%. Northwest India recorded rains about 10% below normal.

District-level data shows that 312 of the 741 monitored districts (42%) received deficient rainfall, with another 38 districts (5%) reporting large deficiencies. Only 290 districts, including all of Odisha, recorded normal rains, while 94 districts saw excess precipitation.

For September, the IMD expects normal rainfall only in parts of Odisha, eastern Madhya Pradesh, Bihar, Jharkhand, eastern Uttar Pradesh, Nagaland, Manipur, Mizoram, and Ladakh. The rest of the country is likely to experience below-average rain.

Meanwhile, a well-marked low-pressure area over Gangetic West Bengal and north coastal Odisha is expected to bring continued rainfall to the region before moving west-northwestwards. Odisha has been an outlier this season, recording a 25% surplus so far. North India, including Delhi, Punjab, Haryana, and Uttar Pradesh, is bracing for widespread heavy rain that is expected to subside by September 5.

Among the most affected states in August were Meghalaya (-58%), Arunachal Pradesh (-41%), Bihar (-40%), Punjab (-36%), and Kerala (-21%).