Rain lashes Bangladesh, more downpour expected today: BMD

Rain lashed almost the entire country for three consecutive days, bringing much-needed respites from uncomfortable hot weather.

"Bangladesh is witnessing rainfall with thunderstorms. We are predicting more rains may occur across the country," said Tariful Newaz Kabir, meteorologist of Bangladesh Meteorological Department (BMD).

Referring to the latest update data from BMD, he said the country will witness moderate to heavy rainfall with thundershowers until next week.

The long-awaited rainfall has brought great relief for the people, particularly the working-class segment of the population, including day labourers.

"The longest spell of heatwave beaching in Bangladesh's history severely affected the lives and livelihoods of the working-class people," Kabir said. 

"Finally, we have received much-needed relief from the deadly heatwave. Bangladesh will not face an extreme heatwave like the previous month of April, which saw a record-breaking heatwave for 28 days, except for two days of the entire month," he added.

"A severe heatwave is unlikely to sweep over the country in May, but a moderate to light heatwave may prevail in southwestern and northwestern regions of the country from the middle of the month," said Omar Faruq, a BMD meteorologist.

On 26 April, Bangladesh set an all-time heatwave record as the Met Office recorded 24 days of heatwave, breaking the previous 23 days in 2019.

"Twenty-three days of heatwave were logged during two months of April and May in 2019, which were considered the longest heatwave in the country's history. But April alone crossed the grim milestone, setting a new record of heatwave days," BMD meteorologist Dr Abul Kalam Mallik said.

Explaining the three key indexes of hot weather — heatwave, severe heatwave, and very severe heatwave — the BMD meteorologist said, "We consider temperatures above 36 degrees Celsius for at least two consecutive days as heatwaves, while temperatures between 40 degrees and 42 degrees are severe heatwaves, and temperatures above 42 degrees Celsius are very severe heatwaves."

The weather expert said earlier that the western and northern regions — Khulna, Rajshahi, and Rangpur of Bangladesh — are considered heatwave-prone areas. 

"Some southwestern parts of Barishal division and Dhaka division experienced heatwave," he continued.

"Since the 90s, the number of days of heatwaves has been increasing alarmingly in Bangladesh, giving a clear signal that the country may face prolonged heatwaves in the future ... Simultaneously, heatwaves are spreading across the country," Mallik added.

"Once, heatwave was confined in the western, northern and central parts of Bangladesh. But this year the entire country is witnessing heatwave. It means weather pattern in Bangladesh has changed drastically extending heatwave coverage areas with its intensity," he added.

According to the BMD data, 18 days of the heatwave were recorded between 13 and 14 April in Dhaka in 1999, 13 days of the heatwave were posted in Dhaka in May 2004, and 18 days, 19 days, and 20 days of a heatwave were recorded in Jashore in 2014, 2016, and 2017, respectively.

The BMD also added that 13, 10, 17, and 13 days of heatwave were reported in 2014, 2016, 2019, and 2022 in Rajshahi, respectively, while 19 and 23 days of heatwave were reported in 2014 and 2019, respectively, in Chudanga.

"Khulna and Rajshahi divisions bore the brunt of the heatwave, as maximum temperatures above 40 degrees Celsius were recorded in most weather stations at the beginning of last month," Bazlur Rashid, a BMD meteorologist, said.

"Finally, Khulna division recorded heavy rainfall since Monday while another hardest-hit Rajshahi region received little rainfall on 6 May," the meteorologist forecasted rainfall is likely to occur in Rajshahi and Khulna divisions.

Jashore and Chuadanga have experienced the highest temperature almost every day since the sweltering heatwave blasted the country at the onset of summer this year, sending the mercury as high as nearly 44 degrees Celsius.

The year's highest temperature, 43.8 degrees Celsius, was recorded in the southwestern district of Jashore on 30 April, while the second highest temperature, 43.7 degrees Celsius, was recorded in another southwestern district of Chuadanga.

Echoing Tariful Newaz Kabir's comments, a BMD meteorologist said that while Bangladesh has been grappling with a brutal heatwave since 1 April, setting a record of prolonged heatwave days, much of the country witnessed significant rainfall with thunderstorms.

Monwar said the mercury has dipped significantly at some weather stations up to six degrees Celsius, meaning cool weather prevails almost throughout the country.

The BMD meteorologist added that, unlike the previous month of April, residents will get respite from blistering heatwaves throughout May as mercury will maintain a tolerable temperature with the impact of rainfall and thunderstorms.

According to the weather bulletin issued by BMD on 7 May, Dhaka city and its adjacent districts recorded a significant amount of rainfall, he said, adding, "The Met Office recorded 97mm at Madaripur, 63mm at Gopalganj."

The bulletin added that the country's highest rainfall was 130 mm in Feni, while 118 mm were recorded in Chattogram, 70mm at Swandip, 57mm at Sitakunda, 89mm at Chandpur, 33mm at Bandarban, 75mm at Khulna, 67mm at Sathkhira, 25mm at Jashore, 75 mm at Barishal, 45 at Patuakhali, 80 mm at Khepupara, 69mm at Bhola, and 63mm at Sylhet.

Monwar said that after mid-May, mild to moderate heat waves will sweep some regions, including Khulna and Rajshahi, and that "We are expecting Bangladesh will not face deadly heat waves like April."

Mallik suggested avoiding staying outdoors during hailstorms, as the intensity of hailstorms is increasing, accompanied by frequent lightning impacted by climate change, which is largely responsible for casualties.

The Met Office recorded 34.6 degrees Celsius at Jashore on 7 May, while the temperature in Dhaka was 32.6 degrees Celsius on the same day.

For the first time, meteorologists acknowledged visibly that climate change caused the erratic weather pattern with gradually expanding areas of heatwave, joining the voice of climate experts and activists