New Delhi, March 5 : The deep depression over Southwest Bay of Bengal moved north-northwestwards on Saturday morning and is likely to shift towards north Tamil Nadu coast by evening bringing light to moderate rainfall therein. The deep depression lay about 350 kms north-northeast of Trincomalee (Sri Lanka), 310 kms east-northeast of Nagappattinam (Tamil Nadu), 300 kms east-southeast of Puducherry (Tamil Nadu) and about 300 kms southeast of Chennai (Tamil Nadu), the India Meteorological Department (IMD) bulletin said. It is likely to move northwestwards till evening and then west-south-westwards towards north Tamil Nadu Coast during subsequent 36 hours. The system has already brought in light to moderate rainfall/thundershower at isolated places over north coastal Tamil Nadu, Puducherry & Karaikal on Saturday while on Sunday, the IMD has forecast, light to moderate rainfall, thundershower at few places with heavy rainfall at isolated places very likely over north coastal Tamil Nadu, Puducherry & Karaikal. It also said light to moderate rainfall or thunder showers at isolated places is very likely over south coastal Andhra Pradesh and Rayalaseema. On Monday, light to moderate rainfall/thundershower at many places with heavy to very heavy rainfall at isolated places is very likely over coastal Tamil Nadu, Puducherry & Karaikal. Light to moderate rainfall or thunder shower with heavy falls at isolated places is very likely over south coastal Andhra Pradesh and Rayalaseema. Meanwhile, squally winds speed reaching 55-65 kmph gusting to 75 kmph would prevail over Southwest & adjoining west-central Bay of Bengal, Gulf of Mannar and along & off north Tamil Nadu, Puducherry & South Andhra Pradesh coasts till Saturday evening. The wind speed would decrease gradually becoming 50-60 kmph gusting to 70 kmph over the same region from Sunday morning and becoming 45-55 kmph gusting to 65 kmph over the same region from Sunday evening. It will further reduce becoming 35-45 kmph gusting to 55 kmph over the same region during Monday. Sea condition will be rough to very rough over Southwest & adjoining west-central Bay of Bengal, Gulf of Mannar and Comorin area and along & off Tamil Nadu, Puducherry & south Andhra Pradesh coasts till March 7 morning, the IMD said and advised fishermen not to venture into south-west & adjoining west-central Bay of Bengal, Gulf of Mannar, Comorin area and along & off Tamil Nadu, Puducherry, and south Andhra Pradesh coasts till Monday morning. /IANS