The very severe cyclonic storm ‘Thane’ over south west Bay of Bengal moved West wards and lay centered about 189 kms south east of Chennai. A met office bulletin issued in Chennai on Thursday evening said that the system is likely to move westwards and cross North Tamil Nadu coast between Nagapattinam and Chennai, close to Puducherry on Friday morning. The bulletin further says that there is a probability of the cyclonic storm weakening slightly before landfall, as it comes further close to the coast.Under the influence of the system, heavy rainfall is likely to commence over North coastal Tamil Nadu, later on Thursday evening. The intensity of the rainfall would increase with heavy to very heavy falls at a few places and isolated extremely heavy falls.Squally weather with wind speed reaching 50-60 kms per hour likely to commence along off coastal districts of North Tamil Nadu and Puducherry.The weather bulletin further warned that extensive damage may be caused to houses with thatched roof and huts along the coast.Tidal wave with height reaching over one meter above astronomical tide could inundate the low lying areas of Chennai, Thiruvallur, Kanchipuram, cuddalore, Villupuram and Nagapattinam districts of Tamil Nadu and Puducherry, when the storm crosses the coast. Great Danger Signal Number ten has been hoisted at Puducherry and Cuddalore ports, while Great Danger Signal number nine has been hoisted at Chennai and Ennore ports.As the Sea would be very rough to high along and off Tamil Nadu coast and Puducherry, Fishermen have been advised not to venture into sea.