The slow moving deep depression may reduce chances of intense rainfall over many districts in the State spread over more than two days.
The Meteorological Department has forecast that heavy rain is likely to occur at one or two places over Villupuram, Cuddalore, Pudukottai and Delta districts, and Puducherry and Karaikal on Sunday and these districts may receive even very heavy rain on Monday. Rain may be light to moderate in coastal areas.
Rainfall activity may cover more districts on Monday and districts such as Ramanathapuram, Thoothukudi, Sivagangai, Chengalpattu, Kallakurichi, Perambalur, Ariyalur and Tiruchi may receive heavy rain in one to two places.
Chennai too has chances of light rain in some areas till Monday.
On Tuesday, rain bands may shift to western ghats districts such as Coimbatore, Nilgiris and Theni and trigger heavy rain there. While rainfall activity may continue till March 9, it would be restricted to isolated places over the State, officials said.
According to the IMD bulletin, the deep depression over southwest Bay of Bengal lay centered at 320 km east-northeast of Nagappattinam and about 290 km east-southeast of Chennai. It is likely to move northwestwards till Saturday evening and then west-southwestwards towards north Tamil Nadu Coast during the next 36 hours.
The weather system may lose intensity and become a depression by Sunday and then further reduce strength to become well marked low pressure area by Monday.
The department has also warned that surface wind with speed reaching 35-45 km per hour is likely to prevail over nine districts, including Chengalpattu, Villupuram, Cuddalore and Ramanathapuram and Puducherry, Karaikal on Sunday and Monday.
S.Balachandran, Deputy Director General of Meteorology, Chennai, said the deep depression’s interaction with the trough in the middle troposphere had delayed its movement and led to variations in rainfall intensity. The influence of westerlies over the system had decreased the rainfall coverage over the State. While coastal areas would experience fairly widespread rainfall on Sunday and Monday, some interior parts may have scattered rains, he added.
