Active Monsoon to Bring Widespread Rain, Ending Mild Heatwave

The persistent, oppressive humidity that has dominated the weather across Bangladesh is expected to clear as the Bangladesh Meteorological Department (BMD) forecasts an extended period of heavy monsoonal rainfall. A comprehensive bulletin released on Sunday, 5 July, by senior meteorologist Dr Md Omar Farooq, indicates that an active southwest monsoon will bring light to moderate showers, alongside isolated torrents of ultra-heavy rain, to almost all divisions over the next five days.

The immediate benefit of this meteorological shift will be a sharp decline in daytime temperatures, which are expected to drop by up to $3^\circ\text{C}$. This cooling trend is anticipated to effectively neutralise the mild heatwave that has been causing widespread discomfort across various districts.

Spatial Distribution of Rain and Temperature Trends

The atmospheric instability will be characterised by temporary gusty winds and frequent electrical storms. Over the initial 24 hours, the monsoonal system will primarily impact the southern, eastern, and northeastern sectors of the country.

The BMD notes that most areas within the Mymensingh, Khulna, Barisal, Chittagong, and Sylhet divisions will see persistent precipitation, with a high probability of heavy to ultra-heavy downpours in isolated pockets. Concurrently, many parts of the northern and central regions, including the Rangpur, Rajshahi, and Dhaka divisions, will experience standard monsoonal showers.

The heatwave, which has been stifling the Rangpur division as well as major districts such as Rajshahi, Pabna, Naogaon, Dhaka, Kishoreganj, Tangail, Mymensingh, Sylhet, Moulvibazar, Rangamati, Chandpur, Feni, Cox’s Bazar, and Chuadanga, is forecast to ease completely during this period.

Extended Five-Day Outlook

The wet spell is projected to intensify and expand in coverage as the week progresses:

• Monday, 6 July: The prevailing pattern will continue, with the heaviest rainfall concentrated over the Mymensingh, Khulna, Barisal, Chittagong, and Sylhet regions. Both daytime and nocturnal temperatures are expected to remain stable.

• Tuesday, 7 July to Thursday, 9 July: The monsoon system will reach its peak distribution. Over these three days, the majority of territories across all eight administrative divisions—Rangpur, Rajshahi, Dhaka, Mymensingh, Khulna, Barisal, Chittagong, and Sylhet—will experience consistent rainfall. The risk of localized ultra-heavy downpours remains high nationwide, with daytime temperatures experiencing an additional minor dip on Tuesday before stabilizing through Thursday.

Broader Environmental Context

Monsoonal transitions in Bangladesh are vital yet complex events. While the arrival of consistent rain is critical for replenishing groundwater levels and supporting the agricultural sector, particularly the cultivation of monsoon-dependent paddy crops, it also brings logistical vulnerabilities.

Heavy rainfall frequently tests the infrastructure of major urban centres like Dhaka and Chittagong, where inadequate drainage systems can lead to rapid waterlogging. Furthermore, the authorities remain alert in topographically vulnerable districts such as Cox’s Bazar and Rangamati, where prolonged, heavy downpours increase the risk of landslides and flash floods. The public has been urged to remain vigilant against lightning strikes during the initial phases of these storms.