Normal rainfall this monsoon, says IMD; below normal, says Skymet

India is likely to witness normal rainfall during the upcoming monsoon season (June–September 2023 period), the country's official weather forecasting agency India Meteorological Department (IMD) has said. The agency's observations come a day after private weather forecaster Skymet predicted a 'below normal' rainy season this monsoon.

IMD's Long Range Forecast of Southwest Monsoon Season Rainfall released today said the monsoon seasonal rainfall is likely to be 96% of the Long Period Average (LPA) with a model error of ± 5%. The LPA of the seasonal rainfall over the country as a whole based on data of 1971-2020 is 87 cm. While IMD categorises 96–104% of LPA as normal, anything between 90–95% of LPA is considered below normal. If the rainfall is below 90% of LPA, it is considered as deficient.

Skymet Weather had forecasted rainfall to be 94% (with an error margin of +/-5%) of LPA during the four month period.

According to IMD, the spatial distribution suggests normal to above normal rainfall likely over many areas of Peninsular India and adjoining East Central India, Northeast India and over some parts of Northwest India. Normal to below normal rainfall is likely over some areas of Northwest India and parts of Westcentral India and some pockets of Northeast India.

"While the IMD has forecast a normal monsoon at 96% of LPA, the probability forecasts suggest a 51% chance of a below normal or deficient monsoon. The volume of rainfall, its timing and dispersion will crucially influence crop sowing and output, as well as prices. Since reservoir levels are healthy by historical standards, a mild delay or sub-par monsoon in June 2023 may not be very challenging. In the event that the monsoon turns out to be below normal, we currently foresee a downside of up to 50 bps to our GDP growth forecast of 6.0% for FY2024," Aditi Nayar, chief economist, Head - Research & Outreach, ICRA Ltd, said.

Meanwhile, IMD stated that the northern hemisphere snow cover areas during February and March 2023 were observed to be below normal. Winter and spring snow cover extent over Northern Hemisphere as well as Eurasia has a tendency of general inverse relationship with the subsequent summer monsoon rainfall, the agency said.

IMD will issue updated forecasts for Monsoon season rainfall in the last week of May 2023.