The India Meteorological Department (IMD) has issued a yellow alert for Chennai and 18 districts of Tamil Nadu for November 18, predicting heavy to very heavy rainfall triggered by a strengthening low-pressure system over the southwest Bay of Bengal. Widespread thunderstorms with lightning and gusty winds reaching 40–50 kmph are forecast to lash coastal and interior areas starting Tuesday morning, with some places likely to record up to 20 cm of rain in a single day.

Northern coastal districts—Chennai, Thiruvallur, Kanchipuram, Chengalpattu, Ranipet, Vellore, Tiruvannamalai, and Villupuram—are expected to bear the brunt of the downpour. The IMD has warned of severe waterlogging in low-lying areas, major traffic gridlock on arterial roads, possible flight disruptions at Chennai airport, and power outages in vulnerable neighbourhoods.

In swift action, district administrations in Chennai and six neighbouring districts have declared a complete holiday for all schools and colleges on November 19. The Tamil Nadu government has placed NDRF and state disaster response teams on high alert, pre-positioned relief materials, and deployed extra dewatering pumps across chronic flooding hotspots like Velachery, Tambaram, and Madipakkam.

Also Read: IMD Warns Tamil Nadu, Puducherry of Intense Heavy Rainfall as Red Alert Issued

Meteorologists say the low-pressure area will move slowly toward the coast and intensify into a depression by Wednesday, prolonging heavy rain over the region until November 20. Though not expected to escalate into a cyclone, the system’s prolonged presence near the shore will dump significant rainfall, keeping the flood risk elevated for the next 48–72 hours.

Authorities have urged citizens to avoid travel unless absolutely necessary, refrain from entering flooded underpasses, and immediately report emergencies to 1070 or 112. As dark clouds gather and the first showers begin, Chennai once again braces for a familiar battle against the rain.

Also Read: Cyclone Montha to Bring Heavy Rain to West Bengal, IMD Issues Warnings