CHENNAI: The Regional Meteorological Centre (RMC) has issued a red alert to nine districts in Tamil Nadu including Chennai and surrounding districts for Wednesday.
It said that heavy to very heavy rain at a few places with extremely heavy rain at one or two places is likely to occur over Tiruvallur, Chennai, Kancheepuram, Chengalpattu, Cuddalore, Villupuram, Mayiladuthurai, Nagapattinam and Tiruvarur districts, Puducherry and Karaikal area.
An extremely heavy rainfall alert is given when there is a possibility of some places in the region receiving more than 20.4 cm of rainfall.
This apart, an orange alert has been issued to Ranipet, Tiruvannamalai, Kallakurichi, Perambalur, Ariyalur and Thanjavur districts for heavy to very heavy rains (11.5 cm to 20.5 cm) for the same day.
The RMC has given an orange alert for the possibility of heavy to very heavy rain in a few places with extremely heavy rain at one or two places in Mayiladuthurai, Nagapattinam and Tiruvarur districts and Karaikal area on Tuesday.
Heavy to very heavy rain is likely to occur at isolated places over Ranipet, Tiruvallur, Chennai, Chengalpattu, Kancheepuram, Tiruvannamalai, Villupuram, Cuddalore, Kallakurichi, Ariyalur, Perambalur and Thanjavur districts and Puducherry on Tuesday.
RMC has also confirmed the formation of a low-pressure area over southeast Bay of Bengal which is expected to become well-marked and move towards north Tamil Nadu in the next two days.