Convective activity aided by a weak trough formed over south coastal Tamil Nadu led to the rainfall

The unexpected spell of rainfall that the city received early Thursday brought with it more problems than cheer to residents who were complaining about sultry weather over the last few days. The meteorological observatory at Nungambakkam recorded 6 cm rainfall during the 24-hour ending 8.30 a.m. on Thursday. The one at Meenambakkam registered 3 cm of rainfall.

The rain gauges at Anna University recorded 7 cm followed by DGP office with 6 cm. According to officials, much of the rainfall was received after 2 a.m. However, the automatic weather stations in Ennore and Madhavaram did not receive much rainfall. Describing this as an unexpected thunderstorm development, officials of the Meteorological Department said convective activity aided by a weak trough formed over south coastal Tamil Nadu led to the rainfall. The department had not expected the revival of rain spell till first week of October.

Water stagnated on many arterial roads, including Sterling Road, Perambur High Road and Jawaharlal Nehru Salai even after a few hours since the rain abated. The impact of rains was evident from the damaged stretches on Third Avenue in Anna Nagar, Nelson Manickam Road in Aminjikarai, Arcot Road, Konnur High Road and Ganesapuram Main Road, Vyasarpadi.

Radhika Shankar, a resident of Ayanavaram, said there has not been much improvement on the road condition in several areas over the years. Water gets stagnated even after a short spell be it Barnaby Road and Rajarathinam Street, Kilpauk or Perambur High Road due to lack of stormwater drain or their poor maintenance. General Patters Road, Royapettah, is a classic example of inundation year after year, she pointed out.

According to Chennai Corporation officials, the problem recurred on GP Road as the road was at a lower level than Anna Salai and the SWD network was nearly 40 years old. Measures are being taken to repair the network.

Though the rainfall had brought down the temperature to normal of 33 degree Celsius, it had affected traffic flow on arterial roads, particularly those with ongoing infrastructure projects, including Erukkancheri High Road. Residents of Vyasarpadi said they had to take a detour as many roads were water-logged.

Compounding the problem for the motorists was the areas where work on storm water drains was underway. Two persons had slipped into the trenches dug for SWD on the water-logged Raja Street in T.Nagar.

Southern suburbs

Heavy rains lashed a few pockets in the southern suburbs, causing immense damage to the already battered arterial roads. Huge quantity of debris was left behind on the carriageway on Grand Southern Trunk in Chromepet after stagnated water receded.

The service lane underneath the bridge of Chennai Bypass over the Tambaram – Somangalam Road was severely damaged, crippling vehicle movement. Heavy vehicles coming from directions – Irumbuliyur, Tiruneermalai, Tambaram and Somangalam – had to wait for a long time to proceed further. The Meteorological Department forecasts that rain or thundershower may occur in some areas on Friday.

(With inputs from K. Manikandan)