Parts of the UK could be hotter than Hawaii on Friday, but forecasters have warned of possible heavy rain and thunder, with more changeable weather to come over the bank holiday weekend.
Temperatures could reach 27C in London and East Anglia at the end of the working week, the Met Office said.
It would make Friday the warmest day of the year so far and hotter than Honolulu, the capital of Hawaii, where highs of 26C are forecast.
“We’ve got some very warm, humid air coming up from the south,” Met Office meteorologist Simon Partridge told the Press Association.
“That means we will see some very warm weather, particularly in the east and the South East, because there we’ll see the best of the sunshine.
“Unfortunately, it doesn’t mean everybody’s going to get a warm, dry, beautiful day.”
Cloud over the central spine of the UK, from Scotland, the Pennines and into the Midlands could produce some heavy rain on Friday.
People enjoy the sun in Charterhouse Square, London (Jordan Pettitt/PA)
PA Wire
“Certainly the odd rumble of thunder is possible there, particularly over the Midlands,” Mr Partridge said.
Fridays highs in London and the South East will be around 10C higher than averages for the time of year, which are 15 to 17C, the Met Office said.
Meanwhile, Cardiff could be warmer than Athens, where forecasters are predicting a high of 14C on Friday, which is 5C cooler than the estimated top temperatures in the Welsh capital.
The warm weather still falls short of the record high in April of 29.4C, which was recorded in Camden Square, central London, in 1949, Met Office records show.
Weather over the May Day weekend will be “a different story” though, with changeable conditions forecast across the UK.
“The weekend is a bit of a different story, really,” said Mr Partridge.
“There will be some bright spells in there as well on Saturday, but there will also be showers, particularly across northern and western parts of the UK.”
Rain is forecast across the country on Sunday and temperatures will continue to cool towards averages for April.
“By the time we get to Monday, we’re actually going to see temperatures roughly where they should be for this time of year,” Mr Partridge said.
“We’re looking at elevens and twelves (degrees Celsius) in the north and fifteens and sixteens in the south, so it will feel quite fresh and chilly compared to what we’ve had.”