Cyclone Montha brings widespread, intense downpour over north Tamil Nadu

Widespread, intense rainfall lashed many parts of Chennai and surrounding districts since Monday night as severe cyclonic storm Montha moved closer to the coast.

The Regional Meteorological Centre (RMC), Chennai, said the severe cyclonic storm lies over westcentral Bay of Bengal, about 190 km south-southeast of Machilipatnam and 340 km south-southwest of Visakhapatnam in Andhra Pradesh.

Read live updates on Cyclone Montha here.

The weather system is expected to cross the Andhra Pradesh coast between Machilipatnam and Kalingapatnam, around Kakinada, on Tuesday (October 28, 2025) evening or night, with a maximum wind speed of 90-100 kmph, gusting up to 110 kmph.

An orange alert has been issued for Tiruvallur district for 24 hours ending 8.30 a.m. on Wednesday (October 29). Eight more districts, including Kancheepuram and Ranipet, are likely to receive heavy rainfall until the severe cyclonic storm makes landfall.

During the past 24 hours ending 8.30 a.m. on Tuesday, several places in extreme north Tamil Nadu received intense downpour. Ennore in Chennai recorded the heaviest rainfall of 13 cm, followed by Virinjipuram in Vellore (11 cm). While Chennai and its neighbouring districts recorded widespread, moderate to heavy rainfall, other districts like the Nilgiris, Coimbatore, Villupuram, and Thoothukudi also received light rainfall.

In its Nowcast valid till 1 p.m., the RMC has forecast moderate rainfall is likely to continue at a few places over Chengalpattu, Chennai, Ranipet, Kancheepuram, and Tiruvallur and at isolated places over Kanniyakumari, Tenkasi, Tirunelveli, Tiruvannamalai, Vellore, and Villupuram. It has also issued an impact warning that traffic may be affected and possibility of waterlogging in some areas.

With another depression remaining practically stationary over Arabian Sea, districts like Theni, Tenkasi, Kanniyakumari, and the Ghat areas of Coimbatore too would receive heavy rains till Wednesday morning.

North coastal and adjoining districts, Puducherry and Karaikal area will experience strong surface winds with speed reaching 30-40 kmph gusting to 50 kmph on Tuesday.

Red Hills floodgates reopened

Meanwhile, the Water Resources Department (WRD) has reopened floodgates of Red Hills reservoir, one of Chennai’s key drinking water sources, to discharge 250 cubic feet per second, following rainfall and increased inflow. Officials of the WRD noted that the minor irrigation tanks located upstream of the reservoir are nearly 95% full and the reservoir received an inflow of 556 cusecs. Water discharge is also being maintained in other two key reservoirs: Poondi and Chembarambakkam.

On Tuesday, Chennai’s six drinking water sources, including Veeranam tank in Cuddalore district, had a total storage of 10.18 thousand million cubic feet against their capacity of 13.22 tmcft. The waterbodies had a combined storage of 6.14 tmcft on the same day last year.

A total of 711 sewer cleaning vehicles, including those hired from other districts, are in operation to clear sewer blocks, according to Chennai Metrowater.