A Foreign Office warning of extreme heat has been issued for Italy as much of southern Europe faces record high temperatures.
The alert came ahead of the summer peak travel period for British holidaymakers as schools in England break up this week.
Red weather alerts have been declared for countries including Italy, Greece, Turkey and Spain with warnings that Sardinia could see temperatures hit a high for Europe of 49C.
The Acropolis in Athens was closed for a third day in succession on Sunday during the hottest periods.
At least 4,000 people were reported to have been evacuated from La Palma in the Canary Islands as a forest fire burned out of control destroying 11,000 acres of land.
Forecasters in Italy warned of an imminent “severe heat storm” as the Italian government issued alerts for 16 cities and advised people to avoid direct sunlight between 11am and 6pm.
Italian meteorologist and climate expert Giulio Betti told the BBC: “Temperatures will reach a peak between 19 and 23 July – not only in Italy but also in Greece, Turkey and the Balkans. Several local heat records within these areas may well be broken during those days,”
Italy’s weather news service Metro reportedly said: “We need to prepare for a severe heat storm that, day after day, will blanket the whole country. In some places ancient heat record will be broken.”
The Foreign, Commonwealth & Development Office updated its travel advice on Friday to say: “Extreme temperatures are currently affecting many areas of Italy.
“For information on hottest areas and how to take care in the heat visit the website of the Italian Ministry of Health (in Italian only) and NHS.”
Meanwhile, soaring temperatures caused by a ‘heat dome’ have led to extreme heat warnings across the US south-west with Las Vegas set for a record high of 47.2C and highs also hitting California, Arizona and Texas.
Other parts of the US face severe thunderstorms and flash floods with the situation in north-eastern states being compounded by poor air quality as the result of ongoing wildfires in Canada.