The Regional centre of the India Meteorological Department (IMD) here has predicted heavy rainfall in Tamil Nadu till July 27.
Heavy rains are likely in Nilgiris, Coimbatore, Tiruppur, Theni, Dindigul, Erode, Krishnagiri, Dharmapuri, Tiruppatur, Salem, Kallakurichi, Karur, Namakkal, Tiruchirapalli, Perambalur, Madurai, Sivaganga, Virudhunagar, Ramanathapuram, Thoothukudi, Tirunelveli, Kanniyakumari and Thenkasi districts.
Chennai and adjoining areas are likely to have cloudy weather on Sunday, and light to moderate rainfall is likely in some areas.
The weather office also warned of thunderstorms and lightning in many parts of the state along with showers.
With the work of stormwater drains still underway, the possibility of inundation in some low-lying areas of the state is worrying the water works department authorities.
The state has received 65 per cent excess rainfall this monsoon season compared to corresponding period previous year.
Chennai has received 79 per cent excess rainfall in the current monsoon season.