Heavy to very heavy rainfall is affecting Chennai and several parts of Tamil Nadu due to a deep depression over the southwest Bay of Bengal, prompting weather alerts from the India Meteorological Department (IMD). Rainfall activity is expected to continue across the state until January 11.
The IMD has issued a mix of yellow and orange alerts in Tamil Nadu. An orange alert has been announced for Thiruvarur, Karaikal and Nagapattinam, indicating the possibility of very heavy rain. Yellow alerts have been issued for Chennai and districts including Thanjavur, Sivagangai, Madurai and Tiruchirapalli, warning of heavy rainfall.
According to the IMD, the deep depression is moving northwestwards and is expected to weaken into a depression before crossing the north Sri Lanka coast by Friday afternoon. The weather system is influencing widespread rain, thunderstorms and lightning across coastal and interior districts of Tamil Nadu.
A high wave alert has been issued for the Nagapattinam and Karaikal coastlines, with sea waves expected to reach heights of up to three metres. Squally weather with wind speeds of 55–65 kmph has also been forecast along the Tamil Nadu coast, Sri Lanka coast and the Gulf of Mannar. Sea conditions are expected to remain rough in the southwest Bay of Bengal and nearby regions.
Fishermen have been advised not to venture into the sea along the Tamil Nadu and Puducherry coasts until January 10. The IMD has also forecast isolated heavy rainfall over Chennai, Chengalpattu, Tiruvallur, Kancheepuram and Villupuram on January 11. Meanwhile, minimum temperatures across Tamil Nadu, Puducherry and Karaikal are expected to remain normal or slightly below normal during this period.