The Bangladesh Water Development Board yesterday forecast a possible flood due to the swelling of the Teesta caused by heavy rainfall in upstream India.

Meanwhile, flash floods in Cox's Bazar and the Bandarbans have also been forecast, as monsoon has begun full-fledged across the country.

Teknaf, Ukhiya, Ramu, Maheshkhali, Kutubdia and some places in Bandarban could be affected due to this flash flood, warns the Flood Forecasting and Warning Centre (FFWC) in a bulletin published on its official website.

"There is no chance of heavy flood this month. But in the first week of July, there will be a flood in the Brahmaputra basin," Arifuzzaman Bhuiyan, executive engineer of the FFWC, told The Daily Star.

The bulletin issued yesterday said there was 114mm of rainfall in Bandarban's Lama upazila in 24 hours till yesterday morning. There was also moderate rainfall recorded in different weather stations in Cox's Bazar.

India's Meteorological Department predicted excessive rainfall in the north-eastern part of Bangladesh and in the bordering areas of India, the bulletin added.

Cherapunji station in Meghalaya recorded 104mm and Gangtok station in Sikkim recorded 85mm of rainfall during this period.

"The water level in the Teesta may cross the danger level at the Dalia point in the next 24 hours," it stated.

The FFWC said the water level of the Ganges river is increasing and it would continue to increase over the next three days.

But it would not cause any floods as the water level of the Ganges is still flowing lower than the danger level.