Forecasters have said parts of the the UK could see a mini heatwave this weekend, with temperatures in London rising towards 30C.
A heatwave is usually declared when the temperature meets the threshold of that area for at least three days in a row - which could happen in the capital.
The threshold for London’s heatwave is 28C and the capital is set to see highs of 24 to 26 throughout the week with lows of below 15.
But according to the Met Office, the weekend will see “plenty of sunshine” and temperatures will rise further.
Met Office spokesman Oli Claydon said: "There's a definition of what a heatwave is - it is at least three consecutive days of maximum temperatures meeting or exceeding a temperature threshold.
"It is above 28C (82.4F) for London and large chunk of the south east, it is 27C (80.6F) for the Midlands and going towards the south west its 26C (78.8F).
"In Northern Ireland, Scotland, Wales, Devon and Cornwall and the north east its 25C (77F) - so it is a sliding scale depending on where you are, but we haven't yet met that maximum threshold."
But the weekend is set to be a scorcher with the mercury potentially tipping 30C (86F) in parts of the South East by the beginning of next week.
Mr Claydon said: "But by the beginning of the weekend and going into next week we might start to meet that criteria, by Sunday we might see 28C (82.4F) or 29C (84.2F).
"It looks set to continue into next week, that is outside of our detailed forecast but the indication is that settled warm weather is set to continue."
Mr Claydon continued: "As well as the 28C/29C (82.4F/84.2F) expected in London and the south east, elsewhere in places like Nottingham will potentially be meeting the heat wave criteria with 27C (80.6F) forecast.
"Various other places set to meet the heatwave threshold as well."
He added: "There's a chance we might get towards 30C (86F) at the beginning of next week."
He added: “For London and the south east in particular most of this week will be fine, dry and sunny and we might just see temperatures slowly pick up. Today we’re seeing 25 to 26C but by Saturday we could see maximums of around 27 to 28C.”
The Met Office also tweeted that high or very high UV levels were expected in many areas across the UK in the coming days, and urged the public to remember sun protection.
Meanwhile, the rest of Wales and England could see temperatures reach highs of 21C to 28C.
In its blog it explained that High-pressure from the Azores will extend across the bulk of the country this week bringing predominantly settled weather and allowing temperatures to slowly rise.
But the start of the weekend could bring some showers in Northern Ireland and western Scotland.