A man refreshes at a fountain in Rome, July 17, 2023. (PHOTO / AP)

ROME – Temperatures were expected to reach record highs in Italy on Tuesday and the World Meteorological Organization warned of an increased risk of deaths as heatwaves and extreme weather gripped parts of Europe, Asia and the United States.

The Mediterranean island of Sardinia could see highs of more than 47 Celsius (116 Fahrenheit) and forecasters said temperatures could hit 40 degrees in several Italian cities, including 42-43 degrees in the Lazio region that includes Rome.

With baking temperatures hitting Europe during the peak summer tourist season, the World Meteorological Organization (WMO) said the heatwave in the northern hemisphere was set to intensify over the coming days and warned of an increased risk to health. An estimated 61,000 people may have died in heatwaves last year in Europe alone.

Heatwaves this summer, which saw temperatures climb to 53 degrees in California's Death Valley, have coincided with wildfires from Greece to the Swiss Alps and deadly flooding in India and South Korea

Heatwaves this summer, which saw temperatures climb to 53 degrees in California's Death Valley, have coincided with wildfires from Greece to the Swiss Alps and deadly flooding in India and South Korea.

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"Temperatures in North America, Asia, and across North Africa and the Mediterranean will be above 40 C for a prolonged number of days this week as the heatwave intensifies," the WMO said.

Overnight minimum temperatures were also expected to reach new highs, the WMO said, creating the risk of increased cases of heart attacks and deaths.

"Whilst most of the attention focuses on daytime maximum temperatures, it is the overnight temperatures which have the biggest health risks, especially for vulnerable populations," it said.

The heat in Europe could also prompt a lasting shift in tourist habits, with more people choosing cooler destinations or travelling in spring or autumn, tourism organizations predicted.

Hottest summers on record

Scientists have long warned that climate change, caused by greenhouse gas emissions mainly from burning fossil fuels, will make heatwaves more frequent, severe and deadly. They say governments need to take drastic action to reduce emissions to prevent climate catastrophe.

The European Union's Copernicus Climate Change Service says 2022 and 2021 were the continent's hottest summers on record. Europe's highest recorded temperature of 48.8C was registered in Sicily two years ago.

In Italy, tourists have tried to keep cool by splashing water on themselves from Rome's fountains and standing under giant fans set up outside the Colosseum. Some were forced to queue for taxis for more than an hour in the scorching heat outside the central railway station in Rome due to the capital's chronic shortage of cabs.

The health ministry has issued red weather alerts – signalling a possible health threat for anyone exposed to the heat – for 20 of the country's 27 main cities on Tuesday, with the number expected to rise to 23 on Wednesday.

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"It is not ruled out that we will exceed 47 degrees, and there could be some places in Sulcis and Campidano (areas in southern Sardinia) that could make us record an even higher value," said Carlo Spanu, from the Italian air force's weather service.

"Our historical record is 47.7 degrees. Nothing prevents us from exceeding or equaling it," he said.

The heat has prompted some travelers to go home early, such as Anita Elshoy and her husband, who returned to Norway from their favorite vacation spot of Vasanello, a village north of Rome, a week earlier than planned.

"(I) got a lot of pain in the head, legs and (my) fingers swelled up and I became more and more dizzy," Elshoy said of her heat-related symptoms. "We were supposed to be there for two weeks, but we couldn't (stay) because of the heat."

In Spain, areas of the northeastern regions of Catalonia and Aragon, and the Mediterranean island of Mallorca were on alert for temperatures of between 42 C and 44 C on Tuesday.

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On Monday, the temperature in the southern city of Andujar reached 44.9 C, while the central city of Toledo broke its maximum temperature record for the month of July, with 42.9 C.

The night was hot, with temperatures not falling below 25 C in many parts of the Mediterranean coast and the interior of the Iberian peninsula, national weather agency AEMET said.

In a large part of the territory, night-time temperatures were in the top 5 percent of the highest recorded at this time of year.

In Greece, authorities have told citizens close to a forest fire in Dervenochoria, north of Athens, to shut doors and windows as smoke from the flames approached amid gale-force winds.