Ten Italian cities were on "red alert" on Thursday amid the country's heatwave, including Sicily's Palermo and the capital Rome, where 40°C was recorded at noon. The health ministry expects a total of 17 cities to be on "red alert" on Saturday.
The sweltering heat is due to a high-pressure system, aptly named Lucifer.
Firefighters have been battling blazes in Sardinia, Sicily and Calabria for weeks. The fire brigade said on Thursday morning that firefighters battled more than 520 blazes during the night, including 230 in Sicily.
The wildfires have killed four people in Italy.
In Sicily firefighters continued to battle blazes as temperatures on Wednesday reached what may possibly be a record high in Europe.
The region's agriculture-meteorological information service (SIAS) reported that the temperature rose to 48.8 degrees Celsius on Wednesday afternoon.
The agency said on its Facebook page that it was the highest temperature registered in the entire network since its installation in 2002.
It may also be a European record, though weather experts cautioned that the measurement still must be confirmed.
Reached by Euronews, a spokeswoman at the World Meteorological Organisation (WMO) said the agency was "actively looking into this observation but at this time we cannot yet confirm or deny its validity," noting the measurement did not come from the official Italian weather service.
"We cannot yet make any preliminary assessment of the 48.8 °C observation, pro or con," WMO told Euronews.
The highest temperature ever recorded on the European continent is 48 degrees Celsius in 1977 in Athens.
Spain and Portugal brace for wildfires
Meanwhile, Spain and Portugal were bracing for the arrival of a dangerous heat wave that has grilled southeastern Europe and is starting to push west toward the Iberian peninsula.
A heatwave fed by hot air from North Africa has engulfed large parts of the Mediterranean region in recent days, contributing to massive wildfires and killing dozens of people in Italy, Turkey and Algeria.
In Greece, huge wildfires have ravaged forests for a week, destroying homes and forcing evacuations.
Portugal’s prime minister warned that the hot weather increases the threat of wildfires, which in 2017 killed more than 100 people in his country.
Spain’s weather service forecast a heatwave through Monday and said temperatures could surpass 44 degrees Celsius in some areas.
“The maximum and minimum temperatures will reach levels far above the normal for this time of the year,” Spain’s weather service, AEMET, said in a “special weather warning.”
Climate change in focus
Such peaks of temperature are not unheard of in Spain and Portugal during the summer months. Even so, climate scientists say there is little doubt climate change from the burning of coal, oil and natural gas is driving extreme events, such as heatwaves, droughts, wildfires, floods and storms.
Researchers can directly link a single event to climate change only through intensive data analysis, but they say such calamities are expected to happen more frequently on our warming planet.
Portuguese Prime Minister António Costa urged people to take special care amid the scorching weather and wildfire danger, adding that many wildfires start with careless behaviour.
Costa said “the terrible images” from Greece and Turkey in recent days brought back Portuguese memories of 2017.
“We don’t want to see that scenario here again,” Costa said in a videotaped message at his official residence.
Portuguese authorities say they can deploy more than 12,000 firefighters, some 2,700 vehicles and 60 aircraft during the summer season.
Costa said that over the past three years Portugal has reduced by half the number of wildfires compared with the average of the previous 10 years and cut the charred area by 64%.
Authorities enacted a broad range of measures after 2017. They included better forest management, including woodland clearance projects and technical support for people living in rural areas, opening thousands of kilometres of firebreaks and reacting more rapidly to outbreaks with special firefighting units.
Nobody has died in forest blazes in Portugal since 2017.