IMD warns of below-normal August rainfall, weaker second half of monsoon

The India Meteorological Department (IMD) on Friday announced that the country is likely to receive below-normal rainfall in August, with precipitation expected to be less than 94% of the long-period average (LPA). The LPA is the average rainfall recorded over a fixed 50-year period, used as a benchmark to compare seasonal rainfall.

The forecast also indicates below-normal rainfall during the second half of the southwest monsoon season, spanning August and September. However, certain regions—including parts of peninsular India, central, eastern, and northeastern India, as well as northern parts of the northwest—may experience normal to above-normal rainfall during this period.

For August specifically, most of the country is expected to see below-normal rainfall, with exceptions in much of eastern peninsular India, parts of northwest and central India, and isolated areas in eastern and northeastern India, where rainfall could be normal or above normal.

The IMD also projected that maximum temperatures across most of the country will remain above normal during August, while minimum temperatures are likely to be normal to above normal in most regions.

The outlook comes after July ended with near-normal rainfall at the all-India level, despite earlier forecasts of a deficit due to the developing El Niño. On June 30, the IMD had predicted a minimum 6% shortfall in July rainfall. However, the country received 101% of the usual amount, helped erase much of the deficit accumulated during June. Still, the distribution of rain was uneven across regions, the IMD noted.

July is the rainiest month of the four-month monsoon season and is critical for agriculture, particularly for the sowing of kharif crops. The variability in rainfall across regions can affect crop health and water availability.

Regarding climatic factors, the IMD said moderate El Niño conditions over the equatorial Pacific are expected to strengthen through the remainder of the monsoon season. El Niño is typically associated with weaker monsoon rainfall in India. In contrast, neutral Indian Ocean Dipole (IOD) conditions are likely to persist before a positive IOD develops during September. A positive IOD often aids monsoon rains, potentially offsetting some adverse effects of El Niño.

For the August–September period, the IMD has forecast rainfall at below 94% of the LPA, suggesting a weaker-than-normal second half of the monsoon. This follows a long-term chart released by the IMD that shows considerable year-to-year variability in August rainfall since 1901, with no strong long-term linear trend in departures from normal over the historical record.

While below-normal rainfall can raise concerns for agriculture and water resources, the forecast does not imply widespread drought, as regional variations are expected. Authorities and farmers are advised to monitor local weather updates and plan accordingly.