

CHENNAI: A depression over the southeast Bay of Bengal is likely to intensify into a deep depression over the next 24 hours and move west-northwestwards towards the southwest Bay, bringing widespread rainfall and heavy spells across coastal Tamil Nadu, Puducherry and Karaikal from January 8 onwards, according to the Regional Meteorological Centre (RMC) here.
On Wednesday, the system was centred about 1,150 km southeast of Karaikal and 1,270 km south-southeast of Chennai. Meteorologists said the system is expected to influence the weather over Tamil Nadu for several days, with rainfall activity peaking between January 8 and 11.
From Thursday, light to moderate rain is likely at isolated to a few places across the State, with heavy rain expected at isolated locations over Ramanathapuram, Pudukkottai, Thanjavur, Thiruvarur and Nagapattinam districts, besides Karaikal. Rainfall intensity is forecast to increase further on January 9, with heavy to very heavy rain likely at isolated places over Nagapattinam and Thiruvarur, and heavy rain over Ramanathapuram, Thanjavur, Mayiladuthurai, Pudukkottai and Cuddalore.
On January 10, heavy to very heavy rain is likely over Cuddalore, Mayiladuthurai, Nagapattinam and Thiruvarur districts, as well as Puducherry and Karaikal, while several northern coastal districts including Chennai, Chengalpattu and Kancheepuram, may see heavy rain at isolated places. Heavy rain warnings continue for parts of north coastal Tamil Nadu on January 11.
For Chennai, partly cloudy skies are expected with light rain likely over the next two days. Meteorologists noted that January cyclonic systems over the Bay are relatively rare, with only 11 cyclonic disturbances recorded during the month between 1961 and 2024, highlighting the unusual nature of the evolving weather pattern.