Italy issued hot weather red alerts for 16 cities on Sunday, with meteorologists warning that temperatures will hit record highs across southern Europe in the coming days.
Spain, Italy and Greece have been experiencing scorching temperatures for several days already, damaging agriculture and leaving tourists scurrying for shade.
But a new anticyclone dubbed Charon, who in Greek mythology was the ferryman of the dead, pushed into the region from north Africa on Sunday and could lift temperatures above 45 Celsius (113 Fahrenheit) in parts of Italy early this week.
"We need to prepare for a severe heat storm that, day after day, will blanket the whole country," Italian weather news service Meteo.it warned on Sunday.
"In some places ancient heat records will be broken."
Greece closed the ancient Acropolis during the hottest part of the day on Friday to protect tourists.
Italy's Health Minister Orazio Schillaci said people needed to take care visiting Rome's famous ruins.
"Going to the Colosseum when it is 43C (109.4F) is not advisable, especially for an elderly person," he told Il Messaggero newspaper on Sunday, saying people should stay indoors between 11 am. and 6 pm.
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