The deep depression which had formed over the south west of Bay of Bengal has intensified into a cyclone named Nelam, which is expected to cross over Nagapattinam and Nellore (South Andhra Pradesh) on Wednesday evening, NDTV reported.
It has already been raining in most of the northern parts of Tamil Nadu including Chennai and the intensity of rainfall is expected to increase from Tuesday evening, with heavy to very heavy rainfall (25 cm or more), according to the Met department.
The Met department bulletin stated earlier on Tuesday, "The deep depression over the south west Bay of Bengal remained practically stationary and lay centred at 0530 hours on the 30 October, 2012 over the south west Bay of Bengal about 500 km south-south east of Chennai and 100 km east-north east of Trincomalee (Sri Lanka). The system would intensify further into a cyclonic storm and move north westwards for some more time and then move north westwards and cross north Tamil Nadu and adjoining south Andhra Pradesh coast between Nagapattinam and Nellore by 31 October, 2012 afternoon/evening."
The bulletin further added that "squally winds speed reaching 45-55 kmph gusting to 65 kmph would prevail along and off north Tamil Nadu, Puducherry and adjoining south Andhra Pradesh coasts during next 12 hours."
The wind speed would gradually increase as the system comes closer to coast.
As the sea condition will be very rough to high along and off north Tamil Nadu, Puducherry and adjoining south Andhra Pradesh coasts during next 48 hours, fishermen have been advised not to venture into the sea.
The government has declared a holiday for schools and colleges on Tuesday.
Image: Satellite image showing deep depression over the south west Bay of Bengal