The Ministry of Health has issued its maximum warning for Rome, Florence, Perugia, Bolzano, Brescia and Rieti on Thursday, when the heatwave gripping much of Europe is expected to reach Italy in earnest.
The heat is set to intensify on Friday, when another ten cities have been warned to be on red alert: Milan, Turin, Venice, Bologna, Naples, Bari, Verona, Frosinone, Latina and Viterbo.
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Photo: Tiziana Fabi/AFP
Temperatures are expected to top seasonal records in the coming days, with up to 41 C predicted in parts of the north-west.
The heat is particularly dangerous for over-75s and children under three, as well as people in poor health. The stifling conditions will worsen air pollution, so those with respiratory problems or allergies are also liable to suffer.
But even those in good physical health are at risk of dehydration, sunstroke, sunburn and exhaustion.
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The health ministry is urging people to take precautions and check on people living alone, as well as urging them not to call the emergency services unless it's essential to avoid an overload on ambulances and hospitals.
The Italian Red Cross has set up a 24-hour hotline that people can call for free for advice and assistance: 800 065 510.
During Italy's heatwave of 2015, so many people died that it lowered the country's average life expectancy that year. And in 2003, Europe's worst heatwave in decades killed 18,000 people in Italy alone.