Chennai, Mar 6 : The Deep Depression over southwest Bay of Bengal weakened into a Depression and moved nearly southwestwards and weakened into a Well Marked Low Pressure Area over the same region at 0830 hrs of today. It is very likely to move further southwestwards towards North Tamil Nadu Coast and weaken gradually into a low pressure area during next 24 hours. Met office sources said under its influence heavy rain is likely to occur at isolated places over Villupuram, Cuddalore, Kallakurichi, Mayiladuthurai, Thanjavur, Tiruvarur, Nagapattinam, Pudukottai, Ariyalur and Perambalur districts of Tamil Nadu and Puducherry and Karaikal area during the next 48 hours. Thunderstorm with lightning is likely to occur at isolated places over Tamil Nadu, Puducherry and Karaikal area for the next two days. Surface wind with speed reaching 35-45 kmph is likely to prevail over Chennai, Tiruvallur, Thanjavur, Tiruvarur, Pudukottai, Ramanathapuram, Chengalpattu, Villupuram, Cuddalore, Mayiladuthurai and Nagapattinam districts of Tamil Nadu, Puducherry and Karaikal area. The 48 hours forecast for Chennai City and its neighbourhood is that the sky condition is likely to be generally cloudy. Light/Moderate rain is likely to occur in some areas. Surface wind with speed reaching 35-45 kmph is likely to prevail over Chennai and neighbourhood. GV 1437