Temperature dips slightly, rain forecast near start of May

The Bangladesh Meteorological Department believes the heatwave has been going on for 28 days

Temperatures have fallen slightly even as a heatwave sweeps through Bangladesh.

The Bangladesh Meteorological Department has also forecast a bit of relief from rain near the start of May.

On Saturday, the mercury hit 42.6 degrees Celsius in Chuadanga, the second-highest temperature on record this summer. Dhaka logged 37.4 degrees Celsius.

On Friday, the temperature had climbed to 42.7 degrees Celsius in Chuadanga, with the mercury rising to 38.2 degrees Celsius in Dhaka.

“There may be rain from May 2,” said meteorologist Omar Faruk. “It may persist for a few days. Then, the temperature will drop.”

Temperatures began to increase at the end of March amid a shortfall of rain. The heatwave started on Mar 31 and intensified slowly.

The BMD has records dating back to 1958, says meteorologist Shaheenul Islam. The longest heatwave on record in those 75 years was 23 days in 2023. It lasted for the final 18 days of April and the first five of May.

“The heatwave started on Mar 31 and has continued since then.”

The current heatwave has already lasted 28 consecutive days, becoming the longest on record.

When the mercury rises to between 36 and 38 degrees Celsius, meteorologists consider it a light heat wave. A moderate heat wave occurs between temperatures of 38-40 degrees Celsius. A severe heat wave occurs when the temperature exceeds 40 degrees Celsius.

Last year, on Apr 17, Pabna’s Ishwardi recorded a temperature of 43 degrees Celsius. It was the second hottest day on record. This year, the temperature has already crossed 42 degrees Celsius a few times.

April is typically quite hot in Bangladesh.

Meteorologist Bazlur Rashid said, “Last year, the humidity was low. This year, due to the high humidity, people are sweating more and they are more uncomfortable. Usually rain falls around this time due to a low pressure system in the west.”

“This year there has been less rainfall. As there has been little rain or Kalbaishakhi storms, the heat is more intense.”

Dr Samrendra Karmakar, former chairman of the National Oceanographic and Maritime Institute, says that May is usually Bangladesh’s hottest month. He recalled that the highest temperature on record – 45.1 degrees Celsius – was recorded in May.

BMD data shows Bangladesh has grown hotter over the past three decades, while rainfall has dropped. It is also warmer for longer periods throughout the year. The average temperature in April has risen too.

Karmakar, a former director at the BMD, said, “Water vapour is supposed to accumulate into rain. But instead of accumulating, it is moving elsewhere. That is why it has gotten hotter.”