Fisherman in Tamil Nadu and Andhra Pradesh were warned on Monday not to go out to sea due to a severe cyclone brewing in the Bay of Bengal.
The storm is 650 kilometres (400 miles) southeast of Madras and is expected to move towards the Indian coast during the next day, meteorological officials said.
"The storm has been stationary for the past 12 hours but it will probably further intensify and move in a northwesterly direction," C V V Bhadram, director at the Hyderabad Meteorological Centre, told AFP.
Cyclone alerts have been sounded in the north of Tamil Nadu and south of Andhra Pradesh and fishermen warned against going out to sea.
"We have already instructed our officials to go out to all the coastal villages and warn the people about taking all necessary precautions against the cyclone," said D C Rosaiah, Andhra Pradesh's relief commissioner.
He said the storm was accompanied by heavy rain and gales of up to 85 kilometres (53 miles) per hour.
Warnings have also been issued in Bangladesh, where the meteorological department warned that waters would remain rough on the coast.
The Bay of Bengal coast is prone to devastating cyclones.
In 1999, a powerful storm hit Orissa, killing at least 10,000 people and leaving millions homeless.
The last major cyclone in Bangladesh was in 1992, killing some 1,35,000 people and causing millions of dollars worth of damage.
In Bangladesh, more than 60 people have died since the start of this month in tropical storms that have also damaged homes, uprooted trees and knocked out power.