A deep depression over the southwest Bay of Bengal is expected to intensify into a cyclone by Wednesday with the India Meteorological Department (IMD) forecasting that it will move towards the Tamil Nadu coast, skirting the Sri Lankan coast over the next two days. As of Tuesday morning, the depression was located approximately 310 km southeast of Trincomalee, 710 km south-southeast of Puducherry, and 800 km south-southeast of Chennai.
The IMD has warned that the system is likely to continue moving north-northwestward and intensify into a cyclonic storm by November 27, after which it will continue towards the Tamil Nadu coast.
Director of Regional Meteorological Centre, Chennai, Dr S Balachandran said, "As of now, yesterday's depression intensifies today morning into a deep depression... It is likely to further intensify into a cyclonic storm and move towards the north direction, towards the Tamil Nadu coast..."
The IMD has issued an orange alert for districts like Chennai, Tiruvallur, and Kanchipuram for Wednesday, anticipating heavy rainfall and thunderstorms. Light to moderate rain, along with thunderstorms and lightning, is expected over Tamil Nadu, Puducherry, and Karaikal.
The heavy rain is likely to be concentrated in Mayiladuthurai, Nagapattinam, Tiruvarur, and Karaikal, with extremely heavy rainfall expected at isolated locations. Villupuram, Cuddalore, Ariyalur, Thanjavur, Pudukkottai, Sivaganga, and Puducherry are also likely to experience heavy to very heavy rainfall at isolated spots, while other areas such as Ramanathapuram, Tiruchirappalli, Perambalur, Kallakurichi, and Chengalpattu are forecast to receive heavy rain at isolated places.
In Chennai, thunderstorms and lightning are expected with moderate rain in certain areas. The IMD has also warned of rough sea conditions along the Tamil Nadu and Puducherry coasts, advising fishermen to stay away from the sea. Coastal areas should prepare for stormy weather as the cyclone develops, with further updates to be issued as the situation evolves.