The UK experienced its hottest day of the year so far on Tuesday and temperatures could reach 30C at the earliest point on record later this week, forecasters said.
The highest temperature recorded on Tuesday was 24.9C in Ross-on-Wye in Herefordshire, according to the Met Office.
The previous hottest day this year was 24.5C recorded in St James’s Park, London, on Monday.
The Met Office, which warned last month that the climate crisis is pushing temperature extremes to new levels, said temperatures could hit 27C or 28C on Wednesday in southern England and the Midlands.
In a further sign of the changing climate, Wales could also set a new record for its highest April temperature – currently 26.2C.
Meteorologist Craig Snell said the most likely places to see the warmest weather on Wednesday were “in a line from London over towards the West Country and into the Midlands”.
Snell told the PA news agency: “The central southern parts of the UK are probably going to be where the highest temperatures will be tomorrow.”
He said Thursday would be “the peak of the heat”, adding: “We are likely to see 28C or 29C, and again it’s going to be a corridor from the west of London over towards Bristol which will probably be the most likely places to see the highest temperatures.”
The meteorologist said the high temperatures on Thursday would result in one of the “warmest starts to May on record”.
Met Office chief meteorologist Paul Gundersen said April temperatures in the mid-20s were “not particularly unusual” but added: “It is more unusual to see temperatures reach the high 20s, and if we see 30C this week, it will be the earliest point in the year in which we have achieved that threshold.”
Temperatures are forecast to drop across much of the UK on Friday as the high pressure starts to pull away.
The highest recorded April temperature was in 1949, when Camden Square, London, recorded 29.4C.
The London fire brigade (LFB) has urged caution around open-water swimming after last month saw a 32% increase in water-related incidents compared with the same period last year.
Craig Carter, the LFB’s assistant commissioner for prevention and protection, said: “Even when the sun is shining, water temperatures can be dangerously cold. Cold water shock can affect anyone, no matter how fit or experienced they are.
“It can lead to water inhalation and, in the worst cases, drowning. Be particularly careful near the water’s edge – it’s easy to slip and fall unexpectedly. And think twice before jumping into open water.”
Research this month found that the number of UK homes overheating in summer quadrupled to 80% over the past decade.
The study also found that the use of air conditioning soared sevenfold to 21% of homes between 2011 and 2022. The researchers warned that continuation of this trend could put strain on the national electricity grid, increase carbon emissions and fuel social disadvantage among families unable to afford air conditioning.
The research was prompted by extreme heatwaves in 2022, when temperatures in the UK rose above 40C for the first time. The past two years have been the hottest on record globally, driven by the burning of fossil fuels.
More than 10,000 people have died as a result of summer heatwaves from 2020 to 2024, data from the UK Health Security Agency shows.
The huge rise in overheated homes and air conditioner use was “a shocking result”, said Dr Mehri Khosravi at the University of East London, who led the study. She added: “Over the heatwaves experienced in 2022 we had nearly 4,500 dead, but this excess mortality is hidden.”
