The low over North Bay and adjoining area moved west-northwestwards and intensified into a well-marked low first and then into a Depression over Northwest Bay and adjoining West Bengal and Bangladesh coast (near lat 21.3°N and lon 89.6°E) at 6am on Friday, according to the Bangladesh Meteorological Department (BMD).
It is likely to move west-northwestwards and cross the West Bengal - Bangladesh coast during the afternoon on Friday.
Due to the depression over Northwest Bay and the adjoining West Bengal and Bangladesh coast, all maritime ports have been advised to keep hoisted local cautionary signal No 3.
The axis of monsoon troughs runs through Rajasthan, Uttar Pradesh, Bihar, West Bengal, the centre of the Depression to Assam across the Southern part of Bangladesh. Monsoon is active over Bangladesh and strong over the North Bay, read the BMD updates.
Moreover, the met office has forecast light to moderate rain in all divisions, including Dhaka of the country in 24 hours commencing 9am on Friday.