Watch: Hottest day of the year so far recorded in all four UK nations
A mini-heatwave is set to continue after all four UK nations recorded the hottest day of the year so far.
Temperatures are expected to rise again on Sunday with the mercury potentially hitting 33C in the south of England.
Health authorities and rescue services have warned people to practise caution in the hot weather, staying hydrated, applying sunscreen and not leaving children or pets in cars.
It comes after thousands flocked to beaches across the country on Saturday.
People in popular coastal hotspots, such as Brighton beach in Sussex and Bournemouth beach in Dorset, were seen cooling off on surfboards and inflatables in the sea.
Meanwhile, the Met Office has said that temperatures could get even higher in England and south Wales on Sunday as the summer heatwave continues.
Tom Morgan, meteorologist at the Met Office, said: "Temperatures are expected to increase even further on Sunday, reaching highs of 33C in the south of the UK."
He added an extended hot spell of weather is expected to last for much of the week ahead, adding: "It's going to mean that people are really going to feel the effects of the heat as we go through this week."
Meanwhile, Public Health England (PHE) and the Met Office have warned people to take care during the hot spell.
PHE urged people to look out for others who may struggle in the heat, such as older people and those who live alone.
It also tweeted: “There is plenty of sunshine forecast across the UK for the next few days. We’re expecting unusually high UV levels over this period, so make sure you don’t get caught out by the strength of the sun.”
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The Royal National Lifeboat Institution has also warned that rivers and lakes are more dangerous this year because water temperatures are colder than normal.
"The forecast for the weekend might be sizzling, but the sea around the UK and Ireland is still low enough to cause cold water shock," the charity tweeted, adding that people who get into trouble should try to stay calm and float until they get control of their breathing.
The RAC has also warned drivers to be careful during a busy weekend on the roads and to check their car is road-ready before setting off.
RAC spokesman Rod Dennis said: “Busier roads, especially in the heat, can mean a sudden sharp increase in breakdowns, so we’re calling on every driver to check their car is ‘road ready’ and isn’t about to let them down.”
The warnings come after schoolboy Matthew Sherrington went missing after he was last spotted playing in the water near Steetley Pier on the Headland in Hartlepool on Thursday, police said.
Humber Coastguard launched an extensive operation, with two Hartlepool RNLI lifeboats searching throughout the night before standing down in the morning.
The coastguard said: “Survivability has been deemed no longer viable. After consultation with police, the search effort has been suspended.”
On Saturday, the hottest day of the year so far was recorded in all four UK nations.
It was the hottest day on record in Northern Ireland with 31.2C recorded in Ballywatticock, in County Down, at 3.40pm, beating the previous highest temperature of 30.8C, reached on 12 July 1983 and 30 June 1976.
In England, 30.3C was recorded in Coton In The Elms, Derbyshire, on Saturday, surpassing the 29.7C recorded in south-west London on June 14.
The year's highest temperatures so far were also recorded in Usk, Monmouthshire, Wales, at 29.6C, and in Threave, in the Dumfries and Galloway region of Scotland, at 28.2C.
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