More than 100,000 people were forced to leave their homes Wednesday as a tropical storm slammed into southern India from the Bay of Bengal, officials say.

The storm left at least two people dead, including a crew member of an oil tanker that ran aground off Chennai, the capital of Tamil Nadu state, the Press Trust of India news agency said.

Rain lashed the region and strong winds uprooted trees in some places. Weather officials said the storm had maximum winds of 75 kilometres per hour after making landfall.

An Indian boy tries to hold his umbrella against strong winds as he walks the Bay of Bengal coast in Chennai, India. The Indian Meteorological Department has advised fishermen not to venture into the open seas due to Cyclone Nilam. (Arun Sankar/Associated Press)

A storm surge of up to 1.5 metres was expected to flood low-lying areas of Tamil Nadu and Andhra Pradesh states, the India Meteorological Department said.

Heavy rain is expected over parts of the states during the next 24 hours. Fishermen were asked to stay at shore until Thursday.

An oil tanker with 37 crew members ran aground off Chennai, the capital of Tamil Nadu state just before the storm hit the shore, PTI reported.

One crew member drowned and coast guard officers were searching for six others whose lifeboat reportedly capsized in the choppy waters as they tried to reach the shore, it said. Officials were not immediately available for comment.

A 46-year old man drowned after he slipped into the sea while walking on a pier as the sea became rough, PTI said.

State authorities turned 282 schools into relief centres in Chennai. The city's port halted cargo operations, officials said. Twenty-three ships were moved to safer areas.

About 150,000 people were moved to shelters in Nellore district in Andhra Pradesh state, a district official said.

In Sri Lanka, authorities said two people were killed and thousands displaced due to heavy rain and strong winds from the storm.

Sri Lanka's Disaster Management Center said 4,627 people across the island nation had been displaced by flooding, while 56 were evacuated in the central region because of threats of landslides. One woman died Tuesday after a tree branch fell on her, while another person was killed in flooding, the agency said. Floods also damaged about 1,000 houses, it said.