Multiple heatwaves, severe storms likely in May

The Bangladesh Meteorological Department has forecast the possibility of multiple heatwaves along with intense Kalbaishakhi storms across the country in May. The department said 2 to 3 days of severe thunderstorms accompanied by squally winds may occur this month.

According to the long-term forecast published on Sunday, May 3, 1 to 3 heatwaves may sweep over the country throughout the month, at least one of which may be severe.

Meteorologist AKM Nazmul Haque said rain-bearing systems will remain active until May 6 to 7. After that, heatwaves are likely to develop over the western and south-western parts of the country.

The month may see 5 to 6 days of light to moderate rainfall, with 2 to 3 of those days bringing severe Kalbaishakhi storms accompanied by thunder, lightning and gusty winds. Hailstorms may also occur in some places .

The forecast also said 1 to 2 low-pressure systems may form in the Bay of Bengal during May. One of them may intensify into a depression and subsequently into a cyclone, with the likelihood of such a weather system developing especially in the latter half of the month .

Day and night temperatures in May are expected to remain near normal overall. Water flow in the country's major rivers is also likely to be normal. However, isolated heavy rainfall may temporarily raise water levels in some rivers in the northern, north-eastern and south-eastern regions.

Analysis of long-term data shows that Bangladesh received 75.7 per cent more rainfall in April than the monthly average. Against a normal average of 119 millimetres, the country recorded approximately 196 millimetres of rain. Division-wise, Barishal recorded 169.5 per cent excess rainfall, Mymensingh 150.9 per cent and Sylhet 104.4 percent.

Meteorologist Nazmul Haque said the interaction between westerly low-pressure systems and easterly winds caused heavy to extremely heavy rainfall throughout April, accompanied by lightning, gusty winds and hailstorms. Thermal low-pressure systems over West Bengal and Bihar, combined with moist air from the Bay of Bengal, led to cloud formation and widespread rainfall across various parts of the country.