Tamil Nadu & Chennai Weather Update: 19 districts will get heavy rains in Tamil Nadu on Friday, the Regional Meterological Centre said in its daily bulletin. Chennai, Tiruvallur, Kancheepuram, Ariyalur and Thanjavur districts have been issued orange alert while Ranipet, Tiruvannamalai, Kallakurichi, Perambalur, Tiruchirappalli, Pudukkottai, Sivaganga and Ramanathapuram districts are on yellow aler