Chennai on Thursday received the highest rainfall among the 32 districts in the state.
The 20% excess rain since June has helped improve groundwater levels, said hydro-geologist J Saravanan of Rain Centre.
The groundwater in K.K. Nagar has risen by one metre, said Saravanan.
Since June, the city (Nungambakkam weather station) has recorded 30cm of rain, 5cm above normal.
Meenambakkam, in the city’s southern suburbs, recorded 39cm rain, 12cm above normal.
Weathermen said rain was likely to continue on Friday.
Rain over the last three days was caused by an upper air cyclonic circulation over the Bay of Bengal near the Tamil Nadu coast.
Area cyclone warning centre director S Balachandran said, “Rainfall is likely to occur across the state until Saturday.”
The light shower that started around 7.30pm on Thursday lasted for about 15 minutes.
The met office has forecast a maximum and minimum temperature of 34°C and 25°C on Friday.
Several areas were water logged for few hours.