HYDERABAD: Hyderabad and various other parts of Telangana recording heavy rains of 10cm to 20cm in a span of just 24 hours is not a sudden deviation in rainfall patterns. In fact, the average rainfall intensity and the number of weather stations recording heavy rains during monsoon season (June-September) have been steadily increasing in the State, according to a report by the Telangana State Development Planning Society (TSDPS).
The average rainfall intensity in 2004 was close to 40mm per day. The value steadily kept increasing. In 2007, 2010, 2011, 2012, 2013 and 2016, it was recorded close to or above 50mm per day. In 2020, it was above 60mm per day. The TSDPS report says, “An annual increasing trend of 0.23mm per southwest monsoon to 0.78mm per southwest monsoon is observed during the last 16 years.”
The report also mentions an increasing trend in the number of weather stations recording heavy and very heavy rainfall days in the period 2004-2020. A higher number of heavy rainfall days have been observed in this period over northern districts (Adilabad, Kumuram Bheem, Nirmal, Kamareddy, Jagtial and Mancherial) and eastern districts (Mulugu, Jayashankar, Bhadradri Kothagudem, Khammam and Warangal Rural), as compared to the southern districts.
The number of stations recording heavy and very heavy rainfall events per day in 2004 was less than five. In 2005, 2006, 2008, 2010, 2014, 2015 and 2017, it was between 5-10, in 2013 and 2016, it was between 10-15, in 2018 and 2019, it was slightly above 15, and in 2020, it was close to 30.