The depression was centred at about 635km southeast of Chattogram port, 575km south-southeast of Payra port, Bangladesh Meteorological Department said in its special bulletin on Wednesday.
Gusts and squalls from 40kmph to 50kmph have been sustained within 44km of the centre of the depression. The sea, however, remains moderate near the centre.
Maritime ports of Chattagram, Coxâ€™s Bazar, Mongla and Payra have been advised to hoist local cautionary signal No. 3.
The low-pressure area over the Bay of Bengal has become ‘well-marked,’ and the latest outlook indicates that it would go on to become not just a depression but will develop further into a deep depression, according to the bulletin.
It is likely to move in a northeast direction and intensity and under its influence steep pressure gradient persists over the North Bay and adjoining areas.
Fishing boats and trawlers in the North Bay area, the system is expected to intensify and move north-northwest. They are advised not to venture into the deep sea.