Bay of Bengal depression strengthens toward severe cyclone, bringing rain to Tamil Nadu

UPDATE - follow-up to Rainfall expected in Tamil Nadu as depression to turn severe cyclonic storm over Bay of Bengal by November 17: A low-pressure system over the Bay of Bengal has strengthened into a depression and is projected to turn into a severe cyclonic storm by November 17, 2026.

Rainfall Forecast And Alerts

Rain is expected in the north coastal districts of Tamil Nadu, along with Puducherry and the Karaikal area. The Regional Meteorological Centre issued a Nowcast alert valid until 4 p.m. for light to moderate rain at isolated spots in Cuddalore, Chengalpattu, Mayiladuthurai, Nagappattinam, Pudukkottai, Thanjavur, Thiruvarur, and Viluppuram districts, as well as Puducherry and Karaikal. Furthermore, moderate rain is likely to reach the western ghats and southern districts starting Monday, November 16. Rainfall already occurred over the past 24 hours in several districts including Chennai, Chengalpattu, Kancheepuram, and Kanyakumari. Meanwhile, Andhra Pradesh has not received any rainfall alerts so far, though a forecast may arrive later in the day.

Storm Movement

The weather system developed from a well-marked low-pressure area over the southeast Bay of Bengal that moved northwestward. It lay centred at 5:30 a.m. and will keep moving northwestward to become a cyclonic storm over the central parts of the south and adjoining west-central Bay of Bengal on November 16, before reaching severe cyclonic storm status on November 17. The India Meteorological Department notes the proposed name for the cyclone is Akwan, as suggested by Iran.

Context

Cyclonic storms frequently form over the Bay of Bengal during the post-monsoon season, often bringing heavy rainfall to India's eastern and southern coastlines. Meteorological agencies track these low-pressure systems continuously to issue timely alerts and help local administrations prepare for potential heavy downpours.