A low pressure is likely to form over the Southeast Bay of Bengal around October 21, the IMD bulletin had warned on Sunday.
Rainfall in the range of 64.5mm to 111.5mm likely over parts of Erode, Nilgiris, Coimbatore, Tiruppur, Dindigul, Theni, Madurai, Virudhunagar, Ramanathapuram, Sivaganga, Pudukottai, Thanjavur, Tiruvarur, Karaikal, Mayiladuthurai, Villupuram, Kancheepuram, Chengalpattu, Cuddalore and Nagapattinam, it said.
Light rain very likely at isolated places also over Salem, Sivaganga, Thanjavur, The Nilgiris, Thiruvallur, Thiruvarur, Viluppuram, Virudhunagar districts of Tamil Nadu districts of Tamil Nadu and over Puducherry and Karaikal area, it added.
Meanwhile, according to TNSMART (Tamil Nadu System for Multi_hazard potential impact assessment, Alert, emergency Response planning and Tracking), in Chennai, Medavakkam received the highest rainfall amount of 102mm on October 19. Kotagiri in the Nilgiris received the highest in the state with 137mm, followed by Kovilankulam in Virudhunagar (135.4mm) and Makkinampatti in Coimbatore (119mm).
Kamatcipuram in Dindigul recorded the least rainfall in the state with 0.2mm.