A low-pressure area has formed over the North Bay and adjoining areas, according to the Bangladesh Meteorological Department (BMD).
The axis of monsoon troughs runs through Uttar Pradesh, Bihar, West Bengal, the centre of the low to Assam across the southern part of Bangladesh, it said.
Monsoon is fairly active over Bangladesh and moderate over the North Bay.
Another low-pressure area may form over the east-central Bay and adjoining North Bay on Wednesday, and it is likely to intensify, the BMD added.
The met office also predicted light to moderate rain or thundershowers accompanied by temporary gusty wind at many places over Khulna, Barisal, and Chittagong divisions, and at a few places over Rangpur, Rajshahi, Mymensingh, Dhaka, and Sylhet divisions, with moderately heavy to heavy falls at places over Khulna, Barisal, and Chittagon divisions.
Day and night temperatures may fall slightly across the country.
