light to moderate rain with Thunderstorm with Lightning is likely to occur at isolated places over Ariyalur, Chengalpattu, Chennai, Kancheepuram, Karur, Madurai, Namakkal, Perambalur, Pudukkottai, Sivaganga, Thanjavur, Tiruchirappalli, Tiruvannamalai, Viluppuram, Virudhunagar in next 3 hours.