Cyclone Thane
A man rides a motorbike on a damaged highway along the Bay of Bengal Sea on the outskirts of Chennai after Cyclone Thane.Reuters

Cyclone storm "Nilam" over southwest Bay of Bengal is likely to make landfall in the coastal areas of Tamil Nadu and Andhra Pradesh on Wednesday evening.

The cyclone is moving north westwards and is positioned about 320 km south-southeast of Chennai and 220 km north of Trincomalee (Sri Lanka), according to The Indian Meteorological Department (IMD).

"Nilam is expected to cross the coast between Cuddalore (Tamil Nadu) and Nellore (Andhra Pradesh) today (Wednesday) evening," Hindustan Times quoted weather official as saying.

The cyclone would move north-north westwards and cross north Tamil Nadu and Andhra Pradesh coast between Cuddalore and Nellore by Wednesday evening.

The two southern states will witness rainfall with scattered heavy to very heavy falls and extremely heavy falls of about 25 cm or more over the next 24 hours. Heavy to very heavy rainfall is also expected to occur over south coastal Andhra Pradesh, Rayalaseema and north Interior Tamil Nadu during the next 48 hours, according to IMD.

As the cyclone edges closer, wind speed is expected to increase and become 80-90 kmph at the time of landfall.

Sea condition will be rough for the next 36 hours along north Tamil Nadu, Puducherry and adjoining south Andhra Pradesh coasts.

"Storm surge of about 1 -1.5 meter over the astronomical tide is likely to inundate the low lying areas of Chennai, Kanchipuram & Tiruvallur of Tamilnadu and Nellore district of Andhra Pradesh," IMD said on its website.

Damages crops like standing rice, groundnut and maize in coastal districts of Tamil Nadu, rice and groundnut in coastal Andhra Pradesh, uprooting of small trees, and minor to power and communication lines are expected as the cyclone approaches the coast.

Fishermen on the coasts are advised on not to venture into the sea over the next 48 hours. Holidays have been declared for schools and colleges in the coastal areas.