Forecasters said the UK had experienced its hottest day of the year so far on Tuesday, with temperatures likely reaching 30c at the earliest recorded late this week.

The highest temperature recorded on Tuesday was 24.9°C in Ross-on-Wye, Herefordshire, according to the Metropolitan Office.

The hottest day of the year on Monday was 24.5c recorded at St James's Park in London.

The Metropolitan Office warned last month that the climate crisis raised extreme temperatures to new levels, saying it could hit 27c or 28c in southern and central England on Wednesday.

Amid further signs of climate change, Wales could also set a new record for the highest temperatures in April (currently at 26.2c).

Meteorologist Craig Snell said the most likely place to see the warmest weather Wednesday is "a line from London to the western country to the central region."

"The central and southern part of the UK will probably be the highest temperature tomorrow," Snell told PA news agency.

Thursday will be a "peak of high temperatures" he said, adding: "We'll likely see 28c or 29c, which will again be the corridor in west London until Bristol, which is probably the place where the highest temperature is most likely to be seen."

The meteorologist said Thursday's high temperatures would lead to the "warmest May start on record."

Paul Gundersen, chief meteorologist at the Metropolitan Office, said April temperatures in the mid-20s were “not particularly unusual” but added: “It’s even more unusual to see temperatures reaching the 20s, and if we see 30c this week, it would be the earliest point we’ll reach the threshold.”

Temperatures are expected to drop in much of the UK on Friday as high pressures begin to escalate.

The highest April temperature was recorded in 1949, when London's Camden Square recorded 29.4c.

The London Fire Brigade (LFB) urged to exercise caution around open water swimming last month, with water-related incidents up 32% compared to the same period last year.

"Water temperature can be dangerous cold water even if the sun shines. The impact of cold water can affect anyone, regardless of their physical health," said Craig Carter, assistant commissioner for prevention and protection at LFB.

"This can cause water to be inhaled, in the worst case, drowning. Be especially careful near the edge of the water - it's easy to slip and fall unexpectedly. Think twice before you jump into open water."

This month’s study found that overheating in the UK during the past decade has accounted for 80% of the number of homes in the summer.

The study also found that the use of air conditioners soared 7 times to 21% of homes between 2011 and 2022. The continuation of this trend could put pressure on the national power grid, increase carbon emissions and facilitate social disadvantages for families who cannot afford the tracheal conditions, researchers warn.

The study was caused by extreme heat waves in 2022, when the UK had temperatures above 40c for the first time. In the past two years, the world's hottest has been driven by the combustion of fossil fuels.

Data from the UK Health Security Agency shows that more than 10,000 people have died due to the summer heat waves between 2020 and 2024.

Dr. Mehri Khosravi, who led the study, said the huge increase in overheated homes and overuse of air conditioners was a "shocking result". "We died nearly 4,500 people in the heat wave experienced in 2022, but this excessive mortality rate is hidden," she added.