A rare weather system in the Bay of Bengal has intensified into a deep depression, bringing significant rainfall to various parts of Tamil Nadu. This event, occurring in January, is considered unusual as the Bay of Bengal has historically witnessed only about 20 intense weather systems in January since 1891. The India Meteorological Department (IMD) has issued orange and yellow alerts, forecasting heavy to very heavy rainfall for coastal and delta districts until January 11, 2026. Areas like Thiruvarur, Nagapattinam, Cuddalore, and Mayiladuthurai are particularly bracing for intense downpours. Even northern districts, including Chennai, are expected to experience heavy rainfall, especially on January 10 and 11. The deep depression, centered over the southwest Bay of Bengal, is projected to move west-northwestwards and is likely to cross the Sri Lankan coast between Trincomalee and Jaffna around noon/afternoon of January 10, 2026. This continued presence of the system indicates a delayed withdrawal of the Northeast Monsoon. Authorities have advised fishermen not to venture into the affected sea areas, including the southwest Bay of Bengal, Gulf of Mannar, and along the Sri Lanka and Tamil Nadu coasts, due to squally weather and rough sea conditions. The unseasonal heavy rains have also sparked concerns among the farming community in the delta districts, as referenced in related reports. This developing weather scenario underscores the importance of public awareness and precautionary measures across the region.