Heavy rainfall may occur in north coastal Tamil Nadu and Andhra Pradesh from the evening of November 14.

Cyclonic storm Gaja has moved westwards and was now located at about 740 km east-northeast of Chennai and expected to cross coastal Tamil Nadu in the afternoon of November 15, the India Meteorological Department (IMD) said today.

A bulletin from the department said Gaja was likely to move west-southwestwards and intensify further into a severe cyclonic storm during the next 24 hours.

"While moving west-southwestwards, it is likely to weaken gradually and cross Tamil Nadu coast between Pamban and Cuddalore as a cyclonic storm in the afternoon of November 15," the bulletin said.

Owing to this, heavy rainfall may occur in north coastal Tamil Nadu and adjoining districts of south coastal Tamil Nadu and Andhra Pradesh from the evening of November 14, it said.

Winds may reach a speed of 70-80 kmph and touch 90 kmph over west-central and adjoining east-central and south Bay of Bengal, the bulletin said.

The gale would gradually sweep at 90-100 kmph and then reach 110 kmph over southwest and adjoining west-central and southeast Bay of Bengal from November 14, it said.

Sea was expected to be rough to very rough along the coast of Tamil Nadu and south Andhra Pradesh and Puducherry from the morning of November 14, the bulletin said.

The waves were likely to rise to about one metre and inundate low-lying areas of Nagapattinam, Thanjavur, Pudukkottai and Ramanathapuram districts of Tamil Nadu and Karaikal at the time of landfall.

Damage was expected in districts of Cuddalore, Nagappattinam, Tiruvarur, Thanjavur, Pudukottai and Ramanathapuram.

Fishermen have been advised not to venture into central and south Bay of Bengal from November 13 to 15.

The Tamil Nadu government has put its machinery on alert and kept around 31,000 rescue personnel on stand-by.

Neighbouring Puducherry was also alerted and precautionary steps were being taken to meet the situation.

The National and State Disaster Response Force personnel have been deployed while vigil has been proposed in coastal districts.

In Pamban, Ramanathapuram district authorities are on an alert and the Collector advised people living in low-lying areas to move to safer places.

Fishermen in Pamban were asked to shift their boats to the 'Chinna Palam' area.

The fisherfolk did not put out to the sea for a third day today owing to the warning issued by the Met department on the likely rough weather due to cyclone Gaja.