An active monsoon system coupled with a steep pressure gradient over the North Bay of Bengal is set to trigger widespread rainfall and severe thunderstorms across Bangladesh over the next five days. The Bangladesh Meteorological Department (BMD) issued a comprehensive weather bulletin warning that all eight administrative divisions will experience gusty winds, frequent lightning, and varying intensities of precipitation, ranging from moderate showers to exceptionally heavy downpours.
The forecast, released by senior BMD meteorologist A.K.M. Nazmul Hoque on Saturday, 11 July, underlines the high probability of localized inundation and flash floods. Given the country’s flat topography and complex river networks, such sustained monsoon activity frequently places a strain on urban drainage systems and rural infrastructure alike.
Chronological Weather Breakdown
The meteorological agency has mapped out the anticipated progression of the weather system, demonstrating how the intense precipitation will initially saturate the entire country before gradually easing by the middle of the week.
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11–12 July (Saturday to Sunday): The initial 24 hours will see maximum coverage, with most areas within the Rangpur, Rajshahi, Mymensingh, Dhaka, Khulna, Barisal, Chittagong, and Sylhet divisions experiencing squalls and electrical storms. Isolated parts of the country are highly likely to suffer torrential rain, though day and night temperatures will remain stable.
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12–13 July (Sunday to Monday): This widespread trend persists into Sunday. Most districts across all eight divisions will continue to experience light to moderate rain, interspersed with very heavy downpours. No significant variation in day or night temperatures is expected.
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13–14 July (Monday to Tuesday): The system will begin to show slight regional variation. While most places in Rangpur, Rajshahi, Mymensingh, Dhaka, Khulna, and Sylhet will remain heavily affected, precipitation will transition to ‘many places’ within the Chittagong and Barisal divisions. The risk of isolated heavy rain remains a nationwide concern.
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14–15 July (Tuesday to Wednesday): Widespread rainfall will remain concentrated across the majority of Rangpur, Rajshahi, Mymensingh, Dhaka, Barisal, and Khulna, whilst shifting to a more scattered pattern across Chittagong and Sylhet. Consequently, maximum daytime temperatures are predicted to rise slightly, while nighttime temperatures hold steady.
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15–16 July (Wednesday to Thursday): By mid-week, the system will begin to lose its intensity. Rainfall will become more localized, covering many areas in Rajshahi, Mymensingh, Dhaka, Chittagong, and Sylhet, but reducing to only a few places in Rangpur, Barisal, and Khulna. Both diurnal and nocturnal temperatures are expected to increase slightly across the country.
According to the weather office, this current spell of heavy precipitation is expected to draw to a close after Thursday, leading to a noticeable reduction in rainfall trends nationwide.
Background Context and Public Advisory
Monsoon Dynamics in South Asia: The stability of Bangladesh’s agricultural economy relies heavily on the moisture-laden winds of the southwest monsoon. However, when these winds are intensified by a pressure differential over the Bay of Bengal, they can precipitate extreme weather events. The immediate aftermath often includes riverbank erosion in rural basins and severe waterlogging in major cities.
Urban centres, particularly Dhaka and Chittagong, face the immediate threat of waterlogging, which historically complicates traffic management and disrupts daily commerce during heavy downpours. Additionally, the maritime community has been alerted; fishing trawlers and boats operating in the deep sea have been advised to navigate with caution near the coast due to choppy waters caused by the atmospheric pressure variance. In northeastern and southeastern hilly regions, such as Sylhet and the Chittagong Hill Tracts, authorities remain vigilant against the risk of rain-induced landslides.
