"Light thunderstorm and lightning with moderate rain are very likely over Chennai, Tiruvallur, Chengalpattu, Kancheepuram, Ranipet and Vellore districts of Tamil Nadu. It is also very likely over isolated places in Tirupattur, Thiruvannamalai, Villupuram and Kanyakumari districts of Tamil Nadu," the Regional Centre said in a release. Chengalpattu, Kancheepuram, Ranipet and Vellore districts of Tamil Nadu. It is also very likely over isolated places in Tirupattur, Thiruvannamalai, Villupuram and Kanyakumari districts of Tamil Nadu," the Regional Centre stated in a release.