New Delhi: The southwest monsoon is likely to be normal across the country as a whole, the India Meteorological Department (IMD) said in its long-range forecast released Tuesday — a day after a private forecaster said the monsoon would likely be below normal.
The IMD, considered the most authoritative forecasting agency in the country, said rainfall during the monsoon months of June, July, August and September is likely to be 96 per cent of the Long Term Average (LPA), falling within the “normal” range.
The LPA — calculated as average rainfall during the season over the country as a whole between 1971 and 2020 — is 87 centimetres. Rainfall is considered below normal if it falls between 90 and 95 per cent of the LPA, according to the IMD.
Variations in rainfall across regions are likely to exist even though rainfall is expected to be “normal” across the country as a whole, the IMD said.
“Normal rainfall is likely over many areas of Peninsular India and adjoining east central India, as well as east and Northeast part of the country, and over some parts of northwest India,” Mrutyunjay Mohapatra, director general of the IMD, said at a press conference.
“Normal to below rainfall is likely over some parts of northwest India and parts of west central India as well as some pockets of Northeast,” he added.
On Monday, private forecaster Skymet Weather said the southwest monsoon was likely to be 94 per cent of the LPA.
An El Nino, a climate phenomenon known to adversely affect the Indian monsoon, is likely to set in later this year.
Any effect the El Nino might have on the monsoon will be visible only during the second half of the season, Mohapatra said, adding that the IMD’s forecast was based on state-of-the art models that use at least six parameters.
“It’s not necessary that an El Nino will lead to a bad monsoon. Of the 15 El Nino years from 1951 to 2022, there were six with normal to above normal rainfall,” Mohapatra said during the press conference.
Other climate phenomena could also mitigate the El Nino’s effect, such as the Indian Ocean Dipole (IOD), which causes differences in sea surface temperatures in the Indian Ocean.
IMD’s climate models forecast a positive IOD development, which could counteract the negative effects of the El Nino. Below normal snow cover over the northern hemisphere could also help India’s monsoon, Mohapatra said.
The IMD will issue an updated forecast in May, ahead of the onset of the southwest monsoon.
(This is an updated version of the story.)
(Edited by Richa Mishra)
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