Maritime ports of Chittagong, Cox's Bazar, Mongla and Payra have been advised to hoist local cautionary signal no-three on Monday.
A Met office weather bulletin said.
A monsoon low over Northwest Bay and adjoining Bangladesh-West Bengal coast has become a well-marked low over the same area and under its influence, steep pressure gradient lies over North Bay.
Squally weather may affect over North Bay, adjoining coastal area of Bangladesh and the maritime ports, according to the bulletin.
All fishing boats and trawlers over North Bay have been advised to remain close to the coast and proceed with caution till further notice.