CHENNAI: The India Meteorological Department (IMD) on Wednesday said the deep low-pressure area over the southeast Bay of Bengal and adjoining equatorial Indian Ocean has intensified into a depression and is likely to strengthen further over the next 24 hours while moving west-northwestwards.

The system had formed on January 5 following an upper-air cyclonic circulation over the central Bay of Bengal and the equatorial Indian Ocean.

According to the IMD, at 11.30 am on January 7, the depression was moving west-northwestwards at about 23 kmph. It was positioned 1,090 km southeast of Karaikal, and 1,220 km south-southeast of Chennai. The system is likely to intensify into a deep depression within the next 24 hours and continue moving west-north westwards towards the southwest Bay of Bengal over the next 48 hours, the IMD said.

Under the influence of the system, light to moderate rain is likely over Tamil Nadu, Puducherry and Karaikal from January 8 to 11, according to the Regional Meteorological Centre (RMC).

Heavy rain is expected on January 8 in Ramanathapuram, Pudukottai, Thanjavur, Tiruvarur, Nagapattinam and Karaikal. On January 9 and 10, Nagapattinam, Tiruvarur, Cuddalore, Mayiladuthurai and Karaikal are likely to see heavy to very heavy rain, with heavy rain also forecast in Ramanathapuram, Thanjavur, Pudukottai and nearby districts. By January 11, heavy rain is likely over Tiruvallur, Chennai, Chengalpattu, Kancheepuram and several northern districts, as well as Puducherry, the weather office forecast.