PARIS (AFP) - France, Spain and other western European nations braced on Saturday (June 18) for a sweltering June weekend that is set to break records, with forest fires and warnings over the effects of climate change.

The weather on Saturday represents a peak of a June heatwave that is in line with warnings from scientists that such phenomena will now hit earlier than usual, thanks to climate change.

Forest fires in Spain on Saturday had burned nearly 20,000 hectares (50,000 acres) of land in the north-west Sierra de la Culebra region.

The flames forced several hundred people from their homes, and 14 villages were evacuated.

Some residents were able to return on Saturday morning, but regional authorities warned the fire “remains active”.

Firefighters were still battling blazes in several other regions, including woodlands in Catalonia.

Temperatures above 40 deg C were forecast in parts of the country on Saturday – with highs of 43 deg C expected in the north-eastern city of Zaragoza.

And more than 3,000 people were evacuated from the Puy du Fou theme park in central Spain due to a fierce fire nearby.

Firefighters were battling fires in several other regions, including woodlands in Catalonia where weather conditions complicated the fight.

Spanish Prime Minister Pedro Sanchez praised firefighters "who risk their lives on the frontline of fires" on Friday, which is also World Day to Combat Desertification and Drought.

There have also been fires in Germany, where temperatures topped 40 deg C on Saturday. A blaze in the Brandenburg region around Berlin had spread over about 60 hectares by Friday evening.

Temperatures in France could reach as high as 42 deg C in some areas on Saturday, French state weather forecaster Meteo France said, adding that June records had already been beaten in 11 areas on Friday.

Farmers in the country are having to adapt. Mr Daniel Toffaloni, a 60-year-old farmer near the southern city of Perpignan, now only works from “daybreak until 11.30am” and in the evening, as temperatures in his tomato greenhouses reach a sizzling 55 deg C.

Hospitals full

More than half of French departments were at the highest or second-highest heat alert level by the afternoon on Friday.

"Hospitals are at capacity, but are keeping up with demand," Health Minister Brigitte Bourguignon told reporters in Vienne, near Lyon in the south-east.

Schoolchildren were told to stay at home in departments at alert level "red", and the health ministry activated a special heatwave hotline.

The Red Cross also organised efforts to distribute fresh water to the homeless community in Toulouse, where temperatures are expected to soar to 38 deg C on Saturday.

"There are more deaths of people in the streets in the summer than in the winter," said volunteer Hugues Juglair, 67.

Meanwhile, rock and metal fans at the music festival Hellfest in western France were sprayed with water from hoses and enormous vaporisers in front of the stage as they headbanged or bounced to an opening-day line-up, including Deftones and The Offspring.

"This is the earliest heatwave ever recorded in France" since 1947, said Mr Matthieu Sorel, a climatologist at Meteo France.

With "many monthly or even all-time temperature records likely to be beaten in several regions," he called the weather a "marker of climate change".

Dutch authorities said they expect Saturday to be the hottest day of the year so far.

The Netherlands’ national meteorological agency has issued a warning for the southern city of Limburg where temperatures could rise to 35 degrees C.

“The elderly and people with vulnerable health can develop health problems due to the heat,” the agency said.

Several towns in northern Italy have announced water rationing, and the Lombardy region may declare a state of emergency as a record drought threatens harvests.

Britain recorded its hottest day of the year on Friday, with temperatures reaching over 30 deg C in the early afternoon, meteorologists said.

It was the third day in a row that temperature records had been broken in Britain, where it was over 28 deg C on Wednesday and 29.5 deg C on Thursday.

Climate change

Experts warned that the high temperatures were caused by worrying climate change trends.

"As a result of climate change, heatwaves are starting earlier," said Ms Clare Nullis, a spokeswoman for the World Meteorological Organisation in Geneva.

"What we're witnessing today is unfortunately a foretaste of the future" if concentrations of greenhouse gases in the atmosphere continue to rise and push global warming towards 2 deg C from pre-industrial levels, she added.

Mr Ibrahim Thiaw, executive secretary of the UN convention charged with reversing land degradation, on Friday warned drought was “set to increase in severity and frequency”.

“The consequences of droughts could affect up to three-quarters of humanity by 2050,” he said during a speech in Madrid.