Fifteen to 20 districts will receive heavy rain from May 16 to 18.

The Nilgiris, ghat areas of Coimbatore, Salem, Dharmapuri, Krishnagiri, Tirupattur, Dindigul, Namakkal, Karur, Tiruchy, Madurai, Sivaganga, Virudhunagar, Tiruvarur, Thanjavur, Nagapattinam, Mayiladuthurai, Pudukkottai, Theni, Tenkasi, Tirunelveli and Kanniyakumari districts and Karaikal area will receive heavy rains till May 20.

The weather department also forecast that in Chennai, the sky will be partly cloudy with the possibility of light rain.

Maximum temperature will be 36-37 degree Celsius and the nighttime temperature will be around 28-29 degrees C for the next two days.

Makkinampatti in Coimbatore received the highest rainfall of 8 cm followed by Pollachi and Thoothukudi port weather stations at 7 cm. Several other weather stations in Virudhunagar, Dindigul, Theni, Nilgiris, Kanniyakumari and Tiruppur received heavy to moderate rainfall.

The maximum temperature in most parts of the state has remained below normal due to the ongoing wet spell which triggered heavy rain.