The low-pressure area over Southeast Bay and adjoining West central Bay moved slightly north eastwards and intensified into a well-marked low over West central Bay and adjoining southwest Bay.
It is likely to intensify further, said a special bulletin of Bangladesh Meteorological Department.
All fishing boats and trawlers over North Bay and deep sea have been advised to come close to the coast and proceed with caution till further notice.
They were also advised not to venture into the deep sea.