BERLIN — A hot air dome blanketed western Europe from the Mediterranean to the Black Sea on Friday, sparking the first heat wave of the season with temperatures expected to top 30 degrees Celsius from London to Paris. .

Meteorologists are warning that this early heat wave is a sign of what lies ahead with continued global warming, which sees extreme temperatures manifest in June that Europe previously only experienced in July or August.

“In parts of Spain and France it’s up to ten degrees warmer – that’s huge – than average for this time of year,” said Clare Nullis, a spokeswoman for the World Meteorological Organization (WMO) in Geneva.

In France, some 18 million people were on Friday under intense heat alerts which affect around a third of the country. Wildfire warnings were in effect from the Pyrenees in the south to Paris.

France has put in place several measures to cope with the heat, since a heat wave killed some 15,000 people in 2003.

On Friday, school children received permission to stay at home in twelve French regions in the south-west and west, where the alert level is the highest. The government is stepping up efforts to ensure that the most vulnerable populations remain well hydrated.

The mercury has been climbing all week in France and is expected to touch 40 degrees Celsius in the south-west of the country on Friday, then in the Paris region on Saturday. The weather is also unusually hot at night. The heat is affecting even normally cooler regions, such as Brittany and Normandy on the Atlantic coast.

Matthieu Sorel, a climatologist with Météo France, told France-Info that several heat records will likely be broken. He warned that this prolonged and early heat wave is a “marker of climate change”.

The UK experienced its hottest day of the year, when the mercury hit 30.7 degrees Celsius at Heathrow Airport mid-day. Britain’s weather service, the Met Office, said it could be up to 34 degrees Celsius in the south of the country ahead of a rainy and cooler weekend.

The Met Office said global warming has inflated the UK’s average summer temperature – and the likelihood of further heatwaves and heatwaves.

“It’s rare to hit 34C in June, but it’s not unprecedented in the UK,” said Mark McCarthy, who heads the Met Office’s National Climate Information Centre. But if it happens this week, it should be noted that it will be produced on three days in the last six Junes.

Prior to 2017, the UK recorded June temperatures above 34 degrees Celsius in 1947, 1957 and 1976.

In Amsterdam, trains to the beaches of the Black Sea coast were very popular in the early afternoon of Friday. Residents and visitors also sought to escape the heat in the city’s famous canals.

Germany’s national weather service predicted the heat will continue through the weekend as the heat wave slides towards central and eastern Europe.

The heat comes after an unusually dry spring in western Europe, to the point where officials have ordered water rationing in northern Italy and parts of France and Germany.

Experts point out that climate change is already disrupting rainfall and evaporation rates in the region, impacting agriculture, industry and wildlife.

“The heat waves start earlier,” said WMO’s Ms. Nullis. They are becoming more frequent and intense due to concentrations of greenhouse gases in the atmosphere, which are reaching unprecedented levels. What we see today, unfortunately, is a taste of the future.”

She recalled that extreme temperatures have been felt elsewhere on the planet in recent weeks. For example, the mercury hovered around 50 degrees Celsius in India and Pakistan.

The heat wave currently affecting Europe began nearly a week ago in Spain, where the mercury soared to 43 degrees Celsius. The Spanish authorities are hoping for a refresh from Sunday.

The heat is also fueling forest fires in Spain, stretching the capabilities of firefighters to their limits.

The heatwave comes as experts and policy makers gather in Madrid to discuss how drought and the spread of deserts across the world could be combated.