The impact of the prevailing weather pattern has contributed to a significant rainfall deficit during the current Southwest monsoon season. Telangana has received 48.8 cm of rainfall so far against the normal 64 cm, translating into a deficit of 24%. Of the State’s 33 districts, 20 remain rainfall deficient.
Senior weather consultant Y.V. Rama Rao said Telangana last experienced a similarly strong El Nino (warming of the central and eastern equatorial Pacific Ocean that can weaken the Indian monsoon) in 1997, when the monsoon rainfall deficit stood at 33%. Another poor monsoon year was 2014, when the overall deficit reached 29%, with monthly deficiencies of 58% in June, 36% in July, 14% in August and 16% in September.
“This year, rainfall was 12% below normal in June and 1% below normal in July. The deficit widened to 38% in August and has remained particularly severe in September (79% so far), when rainfall has been almost absent in many parts of the State,” he said.
Meteorologists classify El Nino conditions as strong when sea surface temperature anomalies in the equatorial Pacific Ocean exceed 1.5C. With the current El Nino reaching around 1.8C, Telangana’s monsoon performance is increasingly resembling that of the drought-prone year of 1997.
Mr. Rao noted that the impact on the rest of India was less severe in 1997 because of a positive Indian Ocean Dipole (IOD), a climatic phenomenon that can enhance rainfall over parts of the country and partially offset El Nino’s influence. However, its benefits are not distributed uniformly and may not significantly aid Telangana. Since 2019, it has been excess rainfall overall especially in August and September months in TG.
Apart from reduced rainfall this year, prolonged clear skies have pushed daytime temperatures 3C to 4C above normal, with maximum temperatures ranging between 35C and 38C. In Hyderabad, temperatures have generally remained 2C to 3C above normal at 33C to 35C. The city has also recorded 37.4 cm of rainfall against a normal 51.5 cm, reflecting a deficit of 27% till date.
But, there could be some relief towards the end of the month. Another low-pressure system is likely to develop over the Bay of Bengal after September 22, potentially bringing widespread rainfall to the State into the first week of October, added Mr. Rao.