The summer's first major heatwave has scorched countries along the northern coast of the Mediterranean, and the sea itself hit a record temperature for the month of June, meteorologists said.

France's national weather agency placed Paris and 15 other departments on its highest weather alert for Tuesday, with temperatures of up to 41 degrees Celsius (105.8 Fahrenheit) predicted.

Ambulances stood ready near tourist hotspots as experts warned that such heatwaves, intensified by climate change, would become more frequent.

In Turkey, rescuers evacuated more than 50,000 people threatened by a string of wildfires. Most were from the western province of Izmir, where winds of 120 kilometres (75 miles) per hour fanned the blazes.

Firefighters also continued to battle blazes that broke out Sunday in Italy, fed by the heat and whipped up by strong winds.

Cities are offering different ways to stay cool, from free swimming pools in Marseille and parks open until 11:00 pm in Bordeaux, to free guided tours for the elderly in Venice's air-conditioned museums.

- Records -

Temperatures in southern Spain soared to 46C on Saturday, a new record for June, the national weather agency said.

The Mediterranean Sea itself was warmer than usual, recording a new June high of 26.01C on Sunday, according to French weather service scientist Thibault Guinaldo, citing data from EU monitor Copernicus.

Agathe Lacombe, a tourist from Strasbourg visiting Madrid with her family, called the heatwave "a bit difficult".

"You have to adapt your whole day's planning, do everything in the morning and come home at the hottest times to find a bit of cool," she told AFP.

Her daughter-in-law, Valentine Jung, said they had not anticipated the heat.

"It's a good thing we've got air-conditioning in our accommodation -- we didn't think of that when we booked," she said.

Portugal's national meteorological agency said Monday the temperature had reached 46.6C in Mora on Sunday, which experts cited by local media said was a new June record.

Seven regions in central and southern Portugal, including the capital Lisbon, were placed on red alert for the second day running Monday, with fire warnings in many forested areas.

In Italy, images posted by local media showed people running into the sea at a beach resort in Baia Domizia near Naples as flames tore through pinewoods behind them.

"I have never experienced anything like this, we were surrounded by flames at least thirty meters high, smoke everywhere," the mayor of nearby Cellole, Guido di Leone, wrote on Facebook.

- Peak -

In France, the heatwave is due to peak on Tuesday and Wednesday, when about 200 public schools plan to close, partially or completely.

No such luck for Italy, where the sizzling temperatures will continue to the end of the week and beyond, according to Antonio Spano, founder of the ilmeteo.it meteorological website.

Authorities have issued red alerts for 18 cities across the country over the next few days, including Rome, Milan, Verona, Perugia and Palermo.

Italy's opposition parties urged the government Monday to improve conditions in the country's stifling prisons, which are notoriously overcrowded.

Scientists say climate change is stoking hotter and more intense heatwaves, particularly in cities where the so-called "urban heat island" effect amplifies temperatures among tightly packed buildings.

It has been particularly bad in Florence and Bologna, which have seen "incessant highs, every day for the whole week", Spano told AFP.

- 'Not normal' -

In Croatia, the vast majority of the coastline was on red alert, while an extreme temperature alert was issued for Montenegro.

And with little relief in sight, the meteorological service in Serbia warned that "severe and extreme drought conditions prevail" in much of the country.

In Madrid, where temperatures approached 40C, 32-year-old photographer Diego Radames told AFPTV he found the June heat "not normal".

"As the years go by, I have the feeling that Madrid is getting hotter and hotter, especially in the city centre," he added.

With temperatures set to rise as high as 34 degrees in London and elsewhere in southwest England, Britain's Met Office weather service upped the number of amber heat alerts Monday to seven regions, as the Wimbledon tennis tournament was getting underway.

It is provisionally the hottest start to Wimbledon on record.

The BBC said temperatures at the All England Club had reached 31.4C by 1500 GMT, surpassing the previous record for the start of the tournament of 29.3C, set in 2001.

"Wimbledon when it's really hot is quite sweaty. Last time we were very hot so this time we've got rose (wine) in a cooler so we can do a better job," Londoner Sean Tipper, 31, told AFP.

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