Heavy rain and thunderstorms will plague parts of the UK in the coming days during a period of tropical and muggy weather.
Showers come in from the Atlantic Ocean will ravage the south and east of the land on Sunday, which will also be hot and humid.
Forecasters say “tropical” conditions will continue through Wednesday, with temperatures reaching into the twenties.
Greg Dewhurst, a With Office forecaster, told the PA news agency: “A changeable picture will emerge in the coming days, with it going to be on the warm and humid side for many.
“Sunday morning looks cloudy, with outbreaks of rain in parts of Wales and central Englandwith heavy showers moving across southern and eastern England, including Londonin the afternoon.
“Most of Scotland and Northern Ireland should remain relatively sunny and dry, while temperatures in parts of England could rise to 27°C.
“It will be hot and muggy and there will be a lot of cloud cover as high pressure builds on Monday. The day starts out sunny and dry before turning wet and windy in the north east and west of the UK.”
Temperatures in London and the south-east could reach 29°C on Tuesday, before turning sunnier and cooler from mid-week.
Mr Dewhurst continued: “There will be a very stuffy feeling, more so at night, so expect an uncomfortable time sleeping, with temperatures in the late teens.”
He said an area of ”tropical maritime air” entering from the south west will hover over the UK in the coming days.
Another forecaster previously told the PA that a “strange rumble of thunder could be heard in isolated areas”.