The IMD forecasts that the system's impact will persist until December 20 with rain continuing in many parts of the Chennai.

Chennai: Rains lashed Chennai and nearby districts of Tiruvallur, and Chengelpet on Wednesday under the influence of a well marked low pressure area over the Bay of Bengal. In view of the widespread rains,

This system is expected to intensify and move west-northwest towards the Tamil Nadu coast on December 18. Heavy rains are likely in isolated places across Chennai, Tiruvallur, Chengalpattu, Kancheepuram, Ranipet, Tiruvannamalai, Kallakurichi, Mayiladuthurai, Nagapattinam, and Tiruvarur districts, as well as Karaikal.

CHENNAI: The Regional Meteorological Centre has revised the heavy to very heavy rainfall alert for Chennai and its surrounding districts for Wednesday, downgrad

Chennai, Tiruvallur, Chengalpattu, and Kanchipuram districts in Tamil Nadu are under an orange alert for heavy to very heavy rainfall on December 18th, potentially causing flooding and disruptions

Pressure Area,' the weather system is expected to intensify into a 'Well marked Low-Pressure Area' and move north-northwestwards towards Tamil Nadu Coasts during the next 2 days, said the IMD.