The rain has brought down the temperature, which was in a rising trend since last couple of weeks. The highest day temperature in the city this month was 37 degree Celsius on April 21. The lowest was 22.5 degree Celsius on April 24.

Most of the city dwellers said the heat is becoming unbearable. "There is no respite from the heat even after evening," commented Abul Bashar, a resident of Mirpur. He said power outages have added to the woes of people.

Excessive heat has led to an outbreak of waterborne diseases, especially diarrhoea. The International Centre for Diarrhoeal Diseases and Research, Bangladesh (ICDDR,B) in Mohakhali is now crammed with hundreds of patients.

Hospital sources said on average 500 patients are coming to the hospital every day. They said 526 patients came on last Friday, most of them from city's Mirpur, Pallabi, Sutrapur, Lalbagh, Kotwali, Sabujbagh, Demra, Khilgaon and Badda areas.

Doctors said people's thirst increases due to extreme heat and they drink water without thinking whether it is pure. "This is why diarrhoea has broken out," said Dr Sarder Nayeem of Japan-Bangladesh Friendship Hospital in Gulshan.

According to met office, rainfall in Dhaka is far less than throughout the country. Before yesterday's rain, the highest rainfall was on April 20 -- only one millimeter.

The summer heat, however, brought a boon to traders selling air coolers as their sale has increased. "We are selling 8 to 10 air coolers a day this year, which was 6 to 8 last year," said Mohammad Noman, branch manager of Butterfly Marketing Ltd.

He said the price of air cooler might go up as the price of compressor has increased in the international market. "Our business is solely dependent in imported compressor."

But the increasing price of air cooler does not matter for slum-dwellers. Bashir Ali, a rag picker, said he takes a dip in the fountain at Bijoy Sarani or at Sonargaon crossing whenever he gets a chance. "Sometimes policemen scold me but I run away."

Not all the poor are lucky like Bashir. The rickshawpullers in the city find it hard to survive in the severe heat. They are forced to pull rickshaws under the scorching sun.

"Sometimes I feel I will be unconscious," said Tayeb Ali, a rickshawpuller living in Katasur area. He said sometimes he takes cheap drinks being sold on the streets.

When asked, officials of meteorological department said the heat would lessen in few days. "Rainfall throughout the country will decrease the heat, we hope," said Asadur Rahman, duty forecasting officer of the department.