An estimated 1,000 fishermen are missing and 15 have drowned after storms hit the Bay of Bengal near the southern coast of Bangladesh.
Saturday's storms brought heavy rains and caused the sea to rise up to 3m (10ft) in coastal areas.
Meanwhile eastern India has been hit by severe flooding and thousands of people have been evacuated because of another series of storms.
The Bay of Bengal often sees storms, especially during the monsoon.
A spokesman for the Fishing Boats Owners Association Golam Mostafa Chowdhury said that only 150 fishermen had been rescued from the sea in Bangladesh.
Most Bangladeshi fishing boats lack communication equipment making them unable to monitor weather conditions.
Weather officials said that the sea would remain rough for a few more days.
In Orissa state in eastern India, 11,000 people have been evacuated from low-lying areas.
State Revenue Minister Manmohan Samal told the BBC that over 25,000 hectares of rice crop have been destroyed by the storm.
Up to 10,000 people were killed by a cyclone in Orissa in 1999
The Indian coastguard helped rescue 33 fishermen off the coast of Orissa, but 13 others are still missing, officials said.
Orissa has been soaked by four days of rain following a storm that formed over the north coast of the neighbouring state of Andhra Pradesh.
There the heavy rains raised the water level in the Godavari river causing extensive flooding in the districts of Khammam, East and West Godavari.
Six people have been reported killed so far in the state, and the Indian Air Force is assisting in search and rescue operations.