A low-pressure area has formed over the Southeast Bay and adjoining regions, and it is likely to intensify, the Bangladesh Meteorological Department said in its bulletin on Friday morning.
Rain or thundershowers are expected at one or two places over the Chattogram and Sylhet divisions.
Elsewhere in the country, the weather is likely to remain mainly dry with partly cloudy skies, the BMD added.
Day and night temperatures may fall slightly across the country.