Shawdesh Desk;

A heatwave set in over 16 districts on Saturday, while heavy rain induced flash flood raged through the north-eastern districts of Sylhet and Sunamganj.

The two completely opposing weather phenomena highlight a seasonal shift, which is attributable to global warming, weather forecasters said.

On Saturday, Moulvibazar, a north-eastern district, just 60 kilometres from the areas swept by the flash flood, was in the list of areas under the influence of the heatwave.

Just three days ago a completely different situation prevailed over the same region with the severe cyclonic storm Remal, accompanied by wind gusting to 100kmph and extremely heavy rain, passing through between May 26 and May 28.

The Remal spurred the onset of monsoon which set in earlier than regular time and advanced to seven out of the country’s eight divisions by Saturday, except for Khulna.

‘We need to observe the situation more. But it can fairly be said that the weather is not consistent with the season’s (monsoon) characteristics,’ said meteorologist Muhammad Abul Kalam Mallik.

Heatwaves occurred more frequently during monsoon since 2000, compared with its previous record in the preceding years from 1981, a study released by the Bangladesh Meteorological Department revealed earlier this year.

Last year, he said, heatwaves recurred during monsoon, which extends from June to September.

Heatwaves, on the other hand, decreased in the pre-monsoon month of March, a trend that continued this year, according to the BMD.

The Flood Forecasting and Warning Centre warned on Saturday afternoon that the flash flood in the north-east region might continue for three more days.

Flash floods that used to be over in hours in earlier days nowadays last for days.

Around seven lakh people are marooned by the flash flood that hit on May 30 with nearly 800 villages inundated in eight upazilas in Sylhet district.

The flash flood affected at least 20,000 people in six villages of Chhatak upazila in Sunamganj on Saturday as the Surma River flowed above the danger mark.

The local office of the Water Development Board said that the Surma flowed 54 centimetres above the danger mark at Chhatak at noon.

The flood is likely to spread to more areas as onrush of water from the upstream continued. The flood situation in Sylhet, however, slightly improved.

Around 4,000 families remained stranded in Sylhet city on Saturday.

‘The flash flood washed away hundreds of houses, many roads, swathes of standing crops and seedbeds of aush paddy, fisheries, ponds and poultry farms,’ Jaintapur upazila chairman Liaquat Ali told New Age.

Goainghat upazila former chairman Abdul Hakim said that they were foreseeing a serious food crisis and pure drinking water shortage unless adequate measures were taken before flood water started receding.

Sylhet district’s relief and rehabilitation officer MA Kuddus Bulbul said that 400 tonnes of rice, 1,250 packets of dry food and Tk 15,50,000 in cash were released for distribution among the flood-hit people.

The FFWC Saturday afternoon bulletin also said that the Kushiyara River was flowing above the danger mark at Amalshid and Sheola, by up to 194cm, while the Surma flowed above its danger mark at Kanaighat and Sylhet, by up to 85cm.

The FFWC said that heavy rainfall continued in Sylhet and its upstream areas in India.

The BMD said that a mild heatwave was sweeping over the districts of Dhaka, Tangail, Faridpur, Madaripur, Rajshahi, Pabna, Sirajganj, Rangpur, Moulvibazar, Chandpur, Noakhali, Bagerhat, Jashore, Barishal, Patuakhali and Bhola and it might abate in some places.

The day temperature is likely to fall by 2C today, the BMD said.

Light to moderate rain accompanied by temporary gusty wind is likely to occur at most places over Rangpur, Mymensingh and Sylhet divisions; at many places over Rajshahi and Dhaka divisions and at a few places over Khulna, Barishal and Chattogram divisions with moderately heavy to heavy falls at places over the country, the BMD said.

Bangladesh’s highest maximum day air temperature of 37.4C was recorded in Jashore on Saturday.