A body of a man from Sheffield was found in a lake on Sunday evening - the fifth person to have died in separate drowning incidents over the weekend.
Emergency services were called to a man coming into breathing difficulties at an unused quarry in Crookes Valley Park, Sheffield, on Sunday evening and pulled the man's body out of the lake.
Three teenagers are among the further four people who died at the weekend, prompting warnings for people to stay safe in hot weather.
One of the teenagers, 16-year-old Mohammad Abdul Hamid, drowned in the River Eden in Cumbria.
He was named by Cumbria Police, who began searching for the teenager after he was reported missing after entering the river near Stoney Holme in Carlisle on Saturday evening.
A second teenager was found dead on Sunday, this time in Salford Quays in Manchester.
Police confirmed that the 19-year-old had died after struggling in the water.
Greater Manchester Police tweeted: "Our thoughts are with this young man's family and friends, and the people who witnessed the tragic events."
Further south, Thames Valley Police confirmed on Sunday that a teenage girl died in hospital after she was found in Ducklington Lake in Witney, Oxfordshire.
And North Yorkshire Police found a body of a man in his 50s in the River Ouse in York on Sunday evening.
Police were alerted by kayakers shortly before 5pm, along with the fire and ambulance services.
The force said: "While formal identification is yet to take place, we believe we know the identity of the deceased but are awaiting confirmation.
"His next of kin have been informed and our thoughts are with them at this very sad time."
England and Wales recorded the hottest day of the year over the weekend, with highs of 31.6C (88.9F) recorded at Heathrow and 30.2C (86.4F) in Cardiff.
It was also the hottest day ever in Northern Ireland on Saturday, with 31.2C (88.16F) recorded in Ballwatticock in Country Down.
The hot weather is set to continue this week, with the Met Office forecasting 32C (89.6F) in some parts of the country.
The Met Office is working with Public Health England (PHE) to ensure that people stay safe in the hot conditions, urging the public to stay hydrated, wear sunscreen and assist anyone who is more vulnerable to the heat.
The extended hot spell of weather is expected to last for much of the week ahead, with temperatures in some parts of the country due to hit the high 20s.