When will the UK heatwave end? Met Office issues forecast for 15C drop in temperature

The Met Office has revealed when the heatwave is likely to end, bringing hope of some relief as the UK continues to suffer extreme heat this week.

Records for the hottest day in June were broken four times on Wednesday as temperatures soared to 36.1C at Gosport in Hampshire.

Cardiff’s overnight temperatures failed to fall below 23.5 degrees, making it the hottest June night on record in the UK.

The red weather warning, which extends from London to Somerset and Swansea, as well as Birmingham, will remain in place until midnight on Thursday.

Given that the exceptionally hot weather will continue into the weekend, the yellow heat warning for the south-east of England has also been extended until 9pm on Saturday.

Train passengers are asked to travel only if “absolutely necessary” on Thursday and Friday in areas worst affected by extreme heat.

The forecaster also said it may be necessary to issue more updates on extreme weather conditions as more details about the conditions become clear.

Met Office spokesman Grahame Madge said: “We issued a further yellow warning for eastern and central England on Friday.

“As forecasts continue to evolve, we may need to issue further updates as more details become clear.”

Temperatures are forecast to exceed 37°C over the next few days, possibly rising to 38°C or even 40°C in some areas, and have already caused disruption to schools and transport networks.

Warm and humid nights will also make it harder to weather this heatwave. Night temperatures in urban areas, known as tropical night, will not fall below 20 degrees.

The fact that the air is very humid makes the heat more effective. Normally the body cools itself through evaporation, but when it is humid the air is already saturated with water vapor and cannot absorb moisture from the skin. This means sweat cannot evaporate and remove heat from the body.

Heat-related health warnings were also issued by the United Kingdom Health Safety Agency (UKHSA), warning that this heat wave could pose a risk even for healthy individuals.

UKHSA Head of Extreme Events and Health Protection, Dr. Agostinho Sousa said: “A red heat health alert indicates a risk to life even for healthy populations, but simple actions such as staying hydrated, avoiding the sun during the hottest part of the day and keeping your home cool can make a big difference.

“It is also important to keep an eye out for others, especially older relatives, neighbors and those with underlying health conditions, to make sure they are aware of the forecast and follow the necessary advice.”

However, the sweltering nights and scorching daytime temperatures will begin to ease over the weekend, with cooler temperatures expected starting Sunday.

Explaining when the heat will start to ease, the Met Office said: “Thursday will see the peak of temperatures for many, but areas further east will retain extreme heat on Friday and Saturday and may continue to see further impacts, which has led to Amber alerts.

“The far south-east will retain the warmth longest, but a drop in figures is expected by Saturday, with highs around 32C likely.

“Next week is likely to see a change towards a more westerly influence on the UK weather, with a return to more average temperatures at certain times of the year and a mix of wind and rain, particularly for those in the North West.”

Temperatures could be 15C cooler by Sunday, according to the Met Office; Highest temperatures are expected to be 26C in London and 20C in Cardiff.