A swathe of the UK stretching from the North West to the South East of England has exceeded the threshold for a heatwave.
The temperature has soared in recent days, hitting 32.2C in Chertsey, Surrey, on Saturday June 10, the highest recorded so far this year.
Porthmadog, north west Wales, saw Tuesday’s highest temperature, at 30.8C.
According to the Met Office, a heatwave is defined as three consecutive days with daily maximum temperatures meeting or exceeding the heatwave temperature threshold.
The threshold varies in each county.
Met Office spokesman Stephen Dixon said the rest of the week will be hotter than average for the time of year, but that the extreme heat may come down slightly, meaning that heatwave criteria may not continue to be hit.
“The heat is set to drop slightly in coming days. London might not meet heatwave criteria, for example, but there’s a good deal of dry, fine, sunny weather to be had this week with temperatures remaining well above average,” he told the PA news agency.
“Into the weekend there should be a fair amount of dry weather, with temperatures remaining warm for many, although also humid and warm overnight.”
Meanwhile, yellow weather warnings for thunderstorms have been issued for northern Scotland and the west of Northern Ireland for Tuesday afternoon and evening, with more rain and thunder possible later in the week.
Mr Dixon said: “On Thursday there is a chance of thunder moving into western areas of Northern Ireland and possibly moving further east into parts of Wales.
“The risk of showers will persist into Friday, but on Thursday and Friday there will still be a good deal of dry weather around, especially in the South East.”
Mayor of London Sadiq Khan extended the current high air pollution warning to those in the capital to Wednesday.
