New Delhi, Mar 2 (PTI) Tamil Nadu, Puducherry and Karaikal are expected to get "heavy" to "very heavy" rainfall for three days beginning Thursday due to a well marked low pressure area in south Bay of Bengal, which is likely to intensify into a depression, the India Meteorological Department said on Wednesday.“The well marked low pressure area over central parts of south Bay of Bengal and adjoining equatorial Indian Ocean is likely to concentrate into a depression by tomorrow (Thursday),” a bulletin by the India Meteorological Department (IMD) said.“It is very likely to move west-northwards towards Sri Lanka coast during the next 24 hours and towards Tamil Nadu coast during the subsequent 24 hours,” it said.The IMD has also issued warnings of high wind speeds and asked fishermen to not venture into South Bay of Bengal and adjoining Equatorial Indian Ocean, Gulf of Mannar and Comorin area till March 5; and southwest and adjoining areas of west central Bay of Bengal and along Tamil Nadu, Puducherry and south Andhra Pradesh coasts on March 3 and March 5.Light to moderate rainfall along with thundershowers at most places, and "heavy" to "very heavy" rainfall at isolated places is very likely over Tamil Nadu, Puducherry and Karaikal during March 3-5, with extremely heavy rainfall at isolated places on March 4, it said.Light to moderate rainfall and thundershowers at most places, and heavy rainfall at isolated places is also very likely over south coastal Andhra Pradesh and Rayalaseema on March 4 and March 5, the bulletin said.The IMD added that sea condition that had been rough over South Bay of Bengal and adjoining Equatorial Indian Ocean, Gulf of Mannar and Comorin area since Wednesday morning is likely to become "very rough" over southwest and adjoining westcentral Bay of Bengal during March 3 to March 5 and along and off Tamil Nadu, Puducherry and south Andhra Pradesh coasts during March 4 to March 5.PTI SKU SRY