The office issued its first-ever “red warning” of extreme heat for Monday and Tuesday, when temperatures in southern England are forecast to reach 37C.
There is a chance temperatures could breach the highest ever recorded in the UK, 38.7C, which was set in 2019.
The weather alert, which covers a big chunk of England from London up to Manchester, warns of danger to life, disruption to air and rail travel and potential “localised loss of power and other essential services, such as water or mobile phone services”.
It comes as Europe battles with extreme heat also.
In the Bordeaux region of southwest France, 10,000 people have been forced to evacuate as thousands of firefighters struggle to contain two wildfires.
In the Spanish city of Seville, one of the hottest spots in Europe this week, some unions called for workers to be sent home.
Temperatures in many parts of Spain have been topping the 40C mark for several days and are expected to continue to do so through to next week.
Seville became the first city in the world to take part in a pilot project that names and categorises heatwaves in an effort to raise awareness of the health hazards caused by extreme heat and the precautions citizens should take.
“Climate-driven extreme heat is killing more people than any other of the climate-driven hazards,” said Kathy Baughman McLeod, director of the Arsht-Rockefeller Resilience Center of the Atlantic Council.
“Heat is invisible, it is silent and it kills slowly, and people are not aware of it.”
