August was driest, warmest month since 1901; monsoon may end with below-normal rain
Rainfall in September is likely to be normal ranging between 91 to 109% of long period average, IMD has forecast.
NEW DELHI: This August was the driest and warmest for the entire country since record-keeping began in 1901.
Monsoon rainfall for August was the lowest in the past 122 years since 1901. Rainfall in August over all of Central India and South Peninsular India was also the lowest since 1901 making it one of the worst months of monsoon deficiency in history, India Meteorological Department said on Thursday.
The all India rainfall was around 191.2 mm this August compared to 192.3 mm in in 1965. Both average maximum and mean temperatures over the country were highest since 1901.
Also Read: How a dry August turned monsoon surplus to deficit
There were two phases of break monsoon conditions in August from August 5 to 16 and August 27 to 31. The monsoon trough was mostly north of its normal condition making it highly unfavourable for rainfall over the plains. “El Nino conditions were very strong which impacted rainfall. Madden Julian Oscillation was also in an unfavourable position,” said M Mohapatra, director general, IMD.
Rainfall in September is likely to be normal ranging between 91 to 109% of long period average, IMD has forecast. Normal to above normal rainfall is most likely over many areas of northeast India, adjoining east India, foothills of the Himalayas and some areas of east-central and south peninsular India. The below-normal rainfall is most likely over most areas of the remaining parts of the country.
According to IMD, above-normal maximum temperatures are likely over most parts of the country, except over some areas in south peninsular India and some pockets of west-central India, where normal to below-normal maximum temperatures are likely. Above-normal minimum temperatures are likely over most parts of the country, except for some areas in extreme north India, where normal to below-normal minimum temperatures are likely.
Altogether monsoon rainfall during 2023 is expected to be “below normal” or lower side of “normal” category officials said. 90 to 95% of LPA is considered to be in “below normal” category while less than 90% is considered “deficient.” Monsoon rainfall between 96 to 104% is considered “normal.” “We are likely to record a below-normal or lower side of normal monsoon rainfall this year but we are not changing our forecast. We had forecast that we were likely to record monsoon rain of 96% with a +/-4% error margin. We will be within that error margin,” said Mohapatra on Thursday.
IMD, the nodal body for weather forecasts in the country, had forecast a “normal” monsoon at 96% (with an error margin of +/-4%) of the long-period average (LPA) in May. The LPA for the monsoon season, calculated on the basis of data from 1971 to 2020, between June to September is 87 cm.
Private weather forecaster, Skymet had forecast a “below normal” rainfall during the monsoon season.
El Nino has a strong influence on the southwest monsoon in India. El Nino years are characterised by an unusual warming of waters in the eastern equatorial Pacific, which has a high correlation with warmer summers and weaker monsoon rains in India.
