Following overnight rains across Chennai, Woods Road in the city is waterlogged on October 21, 2026 | Photo Credit: R. Ragu The Northeast monsoon has become vigorous, bringing heavy overnight rainfall to several parts of Tamil Nadu.
With a fresh weather system taking shape over the Bay of Bengal on Wednesday, widespread rain is likely to continue, particularly over southern and delta districts, over the next few days.The spell of wet weather is expected to continue till October 27, with a low-pressure area forming over the southwest Bay of Bengal, off Tamil Nadu’s coast, during the early hours of Wednesday.Back-to-back weather systems over the Bay of Bengal are expected to sustain intense rainfall across the State this week. Several areas in and around Chennai received heavy overnight downpour, with MGR Nagar in Chennai topping the charts with 15 cm rainfall in the 24-hour period ending 8.30 a.m. on Wednesday.Torrential downpour pounded several areas in Chennai and its fringes, including Vadapalani (14 cm), and brought considerable inflow into the city’s major drinking water reservoirs.
Chennai witnessed heavy rains in the night hours on October 20, 2026. A scene at Anna Salai in Thousand lights | Photo Credit: B.
Velankanni Raj The Central Water Commission has warned of a possible rise in water levels in the Vaigai, Tamirabharani, Bhavani, Noyyal, Aliyar, and Moyar across districts including Coimbatore and Theni till Friday. Above-normal flood situation is expected in rivers such as Kodaiyar and Paralayar in Kanniyakumari and Tenkasi districts, respectively.
Major reservoirs such as Manimuthar and Pechiparai may also receive increased inflow.Another weather systemThe Regional Meteorological Centre (RMC) is monitoring the prospects of another system developing over the Bay of Bengal on October 23.V.R. Durai, head, Regional Weather Forecasting Centre, RMC, said the weather agency was monitoring the intensity and movement of the developing weather system.
While there were chances of the system moving northwestwards and strengthening into a depression, weather models indicated that it may not have much impact on the State, he said.“October systems forming over the Bay of Bengal usually have a tendency to move towards Andhra Pradesh,” he said. Rain lashed Thoothukudi on October 20, 2026 | Photo Credit: N.
Rajesh On Thursday, isolated places in 17 southern, Western Ghats, and delta districts, including the Nilgiris, Tenkasi, Nagapattinam, and Madurai, may receive very heavy rainfall of up to 20 cm. Nine other districts, including Erode, Namakkal, and Cuddalore, may record heavy rainfall.
A similar pattern may continue till October 26.The rainfall intensity may ease over Chennai and its surrounding districts for a few days, and pick up pace on October 25. Overcast sky on the Chennai-Bengaluru National Highway in Ranipet district on October 21, 2026 | Photo Credit: C.
Venkatachalapathy Downgrading of alertOn the downgrading of the red alert for Chennai on Sunday, Mr. Durai said such warnings were issued to facilitate administrative preparedness when exceptionally heavy rainfall occurred and very heavy rainfall was forecast for the following day.
However, the alert was downgraded as the weather system weakened. The technical team of the Greater Chennai Corporation had been advised to examine the city’s weather observation network for discrepancies in rainfall data, he said.
Published - October 21, 2026 01:01 pm IST