LONDON — The weather maps for Europe were blood red on Sunday as heat that has been baking Spain and Italy and fanning fires in southwest France worked its way north toward Britain.
In London, it was warm, in the high 80s, but temperatures on Monday and Tuesday were forecast to hit 100 or higher and to shatter records in a place where air-conditioning is rare and buildings are constructed to retain heat.
In France, the extreme temperatures that have fed wildfires in the south are expected to sweep into the north, especially along the Atlantic coast, which was bracing for uncharacteristically scorching weather.
In Italy, where temperatures were expected to be in the 90s on Sunday, the heat was bad enough, but the country is also experiencing its worst drought in years. The government has allocated 36.5 million euros, about $36.8 million, for water-starved farmers in northern regions. Two hydro-electrical plants had to be shut in the area because there was not enough water to cool them.
And in Spain, a heat wave entered its eighth day, with 30 wildfires burning across the country. Relief is hard to find, even after the sun goes down — Saturday night was Madrid’s fifth consecutive “torrid night,” a term used when temperatures do not fall below 77 degrees Fahrenheit. The previous record stood at three nights. Rubén del Campo, the State Meteorological Agency’s spokesman, said that of the 27 torrid nights recorded in the past century, over half, 15, were since 2012.
Like everywhere else on Earth, Europe is seeing more extreme weather events more frequently, partly as a result of climate change. For proof, one has to look back only to last summer, when floods washed through Germany and other countries in July, killing hundreds. In August, multiple wildfires consumed large areas of Greece. And, also in August, one town in Sicily may have recorded the hottest temperature ever in Europe: 124 degrees Fahrenheit.
But on Sunday, the attention in France was focused on the wildfires, in the southwestern Gironde region near Bordeaux, where over 1,200 firefighters were still struggling to contain two separate blazes.
The fires have destroyed over 25,000 acres of vegetation and have forced more than 14,000 people to evacuate since Tuesday, the local authorities said.
Four firefighters so far have been slightly injured, they said, and damage to buildings and homes has been minimal. Still, the authorities warned that the situation was unstable, with higher temperatures and shifting winds expected on Monday.
“The weather conditions are very, very bad,” Vincent Ferrier, a local official in Langon, an area of Gironde, told reporters on Sunday. “These are obviously the worst conditions that you can have when you are fighting against a fire.”
In Rome, where it has been in the 90s for the past week, street vendors dozed in the shade on Sunday morning while tourists filled their water bottles from the famous fountains.
“It’s hot — too hot to walk around during the day,” said Serena Vendoni, 57, a hairdresser from northern Italy who was visiting Rome with her family for a long weekend. “But it’s hot even at home. We have been turning on the A.C. every day and every night for almost two months now.”
She said that her family’s electric bill had skyrocketed as temperatures had rarely been under 86 for weeks.
“We want to be careful with the A.C.,” Ms. Vendoni said. Energy prices have shot up in Europe partly because of the war in Ukraine. “But we have to be able to live in the house — and sleep.”
On Sunday in Britain, people were making their own plans to withstand the coming heat. The forecasts for Monday and Tuesday were dire — on Friday, the country’s national weather service issued the most severe warning it has for London and a large part of England.
The warning, a “red” alert, is meant to convey a risk to life, and health officials stressed that even healthy people could be adversely affected. The public was warned to try to stay out of the sun from 11 a.m. to 3 p.m., to make only essential journeys on those days, to avoid exercising during the hottest part of the day and to carry water with them.
Reporting was contributed by Aurelien Breeden from Paris, Francheska Melendez from Foz do Farelo, Portugal, Gaia Pianigiani from Rome and Euan Ward from London.