An extreme heatwave that has brought scorching temperatures to most parts of the country in recent days was expected to continue gripping the peninsula this week, according to the latest forecasts.

Hot and muggy conditions were forecast to further intensify just before the Ferragosto holiday, on Thursday, August 15th, with the mercury set to shoot up to highs of 38C to 40C in mainland areas and on the two major islands Sicily and Sardinia. 

As experts earlier this week warned of a Ferragosto infuocato (or ‘fiery Ferragosto’), Italian health authorities placed some 22 of Italy’s 27 major cities under the maximum heat alert on Wednesday, August 14th. 

The highest-level alert for the 22 urban centres was then extended to cover the Ferragosto holiday under an update published on Tuesday morning.

While bouts of hot weather are far from rare during summer in Italy, prolonged spells of particularly hot and humid conditions can pose a risk to human health, especially when temperatures remain high overnight as part of a phenomenon known as ‘tropical night’.

What do Italy’s heat warnings mean?

To warn of the potential health threat posed by prolonged spells of hot weather, Italy’s health ministry issues three-day alerts, updated daily, with heat risk levels for the country’s 27 major urban centres.

A red alert is the highest-level warning, which the ministry says signifies a potential health risk to the general population.

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This is followed by amber for medium-high risk and yellow for a medium-low level alert, which means there are risks to more vulnerable groups in society, including children, people affected by chronic illnesses and the elderly.

Green is level zero, signifying no heat risk.

Heat warnings on Wednesday and Thursday:

Some 22 of Italy’s 27 major urban centres were set to be under the maximum heat alert on Wednesday, August 14th, and Thursday, August 15th. 

The list included Venice, Bologna, Milan, Florence, Rome and Palermo. 

Only five major cities around the country – Catania, Messina, Reggio Calabria, Pescara and Civitavecchia – were set to be under a lower-level yellow alert on those days. 

How long will the current heatwave last?

Long-term weather projections released on Monday indicated that the current heatwave should only start easing off from the late afternoon or evening of Saturday, August 17th, when an area of cool air moving down from northern Europe is expected to bring rain storms and lower temperatures in the north and centre of the peninsula. 

Daytime temperatures in the south of the boot and on Italy’s major islands Sicily and Sardinia are also expected to cool off as a result of the upcoming front, though rainfall may not be as intense as in the north, or even totally absent in some areas.