A low-pressure system over the northwest Bay of Bengal and adjoining coastal regions has intensified into a well-marked low and is expected to strengthen further, the Bangladesh Meteorological Department (BMD) reported on Monday morning.
According to BMD’s latest weather bulletin, the southwest monsoon—which typically brings a season of sustained rainfall to the subcontinent—has now advanced into Barishal, Chattogram, Sylhet, Mymensingh, and the eastern parts of Dhaka division. The monsoon’s progression signals the onset of the rainy season in many parts of the country, potentially easing the heat but also raising concerns over localized flooding and disruptions.
In its 24-hour forecast beginning at 9:00 AM today, the meteorological office predicted light to moderate rain or thunderstorms at most places in Mymensingh, Dhaka, Khulna, Barishal, Chattogram, and Sylhet divisions, often accompanied by temporary gusty winds and lightning flashes. The divisions of Rangpur and Rajshahi may also see scattered showers, although on a lesser scale.
More intense rainfall is likely in specific areas of Khulna, Barishal, Chattogram, and Sylhet, where moderately heavy to very heavy downpours are forecast. The rains, though beneficial for agriculture and groundwater replenishment, may temporarily disrupt road transportation, cause waterlogging in urban centers, and trigger river level rises in flood-prone regions.
In a special advisory, the BMD cautioned that the intensifying weather system could lead to gusty or squally winds affecting the maritime ports, North Bay, and adjoining coastal areas of the country. The advisory emphasized the need for preparedness in vulnerable coastal regions, where fishing and maritime activity are common livelihoods.
As a result, maritime ports in Chattogram, Cox’s Bazar, Mongla, and Payra have been instructed to hoist local cautionary signal No. 3, indicating potentially hazardous conditions at sea. In addition, all fishing boats and trawlers operating in the North Bay have been advised to remain close to shore and exercise heightened caution until further notice.
The BMD also issued an extended outlook for the coming 96 hours (four days), indicating continued widespread rainfall activity across the country. During this period, the national day and night temperatures are expected to drop slightly during the first 24 hours, followed by stable temperatures over the next 48 hours, and then a slight rise in the final 24-hour stretch of the forecast window.
In terms of recent climate observations, Sylhet recorded the highest maximum temperature in the country yesterday at 38.4°C, while Dhaka experienced a maximum temperature of 35.6°C, reflecting the ongoing seasonal heat across the plains.
Meanwhile, the highest amount of rainfall in the past 24 hours, measured until 6:00 AM today, was recorded at Ambagan in Chattogram, where 27 millimeters of rain fell, providing early signs of the monsoon’s arrival in southeastern regions.
As the monsoon season begins to take hold, authorities are urging residents, especially in coastal and low-lying areas, to remain alert and monitor official weather updates regularly.
