Bangladesh Rainfall Surpasses Normal Levels in April

The Bangladesh Meteorological Department (BMD) has released its long-term forecast for May, revealing that the country experienced significantly higher rainfall than average during the month of April. According to the report, nationwide precipitation was more than 75% above the seasonal norm, a factor that contributed to maintaining temperatures below typical levels for what is traditionally the hottest month of the year.

April Climate Analysis and Regional Variations

In a standard year, April is identified as the warmest month in Bangladesh, with a mean temperature of $33.2$°C. However, the recently concluded April saw the maximum and average temperatures remain $0.6$°C and $0.1$°C lower than normal, respectively. This cooling effect is directly attributed to the frequent rainfall recorded across various divisions.

The Barisal Division recorded the highest increase, with rainfall exceeding the norm by 169%. Dhaka Division followed with an approximately 80% increase. In contrast, the Rajshahi Division recorded rainfall slightly below the seasonal average.

The following table outlines the temperature and rainfall statistics for April:

Heatwave Trends and Classifications

While April 2024 was marked by a continuous, month-long heatwave, April 2025 saw only isolated and intermittent heat events. A heatwave began early in the month but subsided within two days due to the onset of rain. A second spell lasted approximately seven days, affecting a maximum of 22 districts.

The BMD employs specific terminology to classify these thermal conditions:

• Mild Heatwave: $36$°C to $37.9$°C

• Moderate Heatwave: $38$°C to $39.9$°C

• Severe Heatwave: $40$°C to $41.9$°C

• Very Severe Heatwave: $42$°C and above

Projections for May

May is historically the second warmest month in the region. The BMD anticipates a return to normal rainfall patterns this month. However, the forecast indicates the potential for significant weather events, including one to two low-pressure systems, which could potentially develop into a depression or a cyclone, though officials suggest the likelihood of a major cyclone remains low.

Additionally, five to six Nor’westers (Kalbaishakhi storms) are expected, with two to three predicted to be severe. Regarding heat, the department forecasts one to three mild-to-moderate heatwaves, with the possibility of one severe heatwave.

Senior Meteorologist Md. Bazlur Rashid noted that intermittent rain is likely to persist until May 10, keeping temperatures stable. A gradual rise in temperature is expected thereafter, with a possible heatwave period of six to seven days commencing after May 15. Despite these spikes, the overall temperature for the month is expected to remain relatively tolerable.