The Regional Meteorological Centre (RMC) here on Sunday forecast heavy rains at isolated places in several districts for four days beginning Tuesday.This is due to the influence of an upper air cyclonic circulation over Southeast Bay of Bengal, between 3.1 km and 5.8 km above mean sea level.According to B. Amudha, Head, (Additional in-charge), RMC, a cyclonic circulation over Southeast Bay of Bengal is likely to draw moisture and influence rainfall activity from Tuesday. “We are watching the circulation, and will provide necessary updates. Saturday’s trough from South interior Karnataka to Gulf of Mannar across Tamil Nadu, at 0.9 km above mean sea level, has become less marked, which is why we had mostly dry weather till Sunday evening,” she said.On Tuesday, heavy rain is likely to occur at isolated places over Erode, Krishnagiri, Dharmapuri, Tirupattur, Salem, and Vellore. For Wednesday, heavy rains have been forecast in Krishnagiri, Dharmapuri, Salem, Tirupattur, Vellore, Ranipet, Kancheepuram, Chengalpattu, Tiruvannamalai, Kallakurichi, Villuppuram, and Puducherry.On Thursday, isolated places over districts including Salem, Tiruvannamalai, Kallakurichi, Villuppuram, Cuddalore, Chengalpattu, Kancheepuram, Ariyalur, Perambalur and Mayiladuthurai districts and Puducherry are likely to get heavy rains. On Friday, rainfall activity is likely to reduce and heavy rain may occur at isolated places over Tiruvallur, Ranipet, Vellore and Kancheepuram districts.Meanwhile from Monday, it has predicted light to moderate rain at a few places with thunderstorm and lightning at one or two places over Tamil Nadu, Puducherry and Karaikal area. Published - September 14, 2025 11:46 pm IST