Red alert for 27 cities as fourth heatwave tests Florence's fragile stones

Italy is to place all of its 27 major cities, from Trieste in the north to Palermo in the south, under the highest heat alert as the fourth heatwave to hit the country this summer intensifies, according to the Guardian. The red alert covers every major urban centre, including Florence, where temperatures are edging close to 40C.

The alert, issued as the summer's fourth heatwave peaks, places the entire peninsula under the same extreme-weather warning. For Tuscany's capital, the timing is acute: August is the month of peak tourist volume, when the Uffizi and the Duomo draw their largest crowds of the year.

The Guardian's report notes the heatwave has been building for weeks, with little respite expected in the coming days. The red alert is the highest level of the Italian heat warning system, signalling a health risk to the general population, not just the vulnerable.

For Florence, the heat alert arrives at the worst possible moment for its heritage economy. The city's historic centre, a UNESCO World Heritage site, is built from stone and marble that absorb and radiate heat, turning the narrow streets of the Oltrarno and the Piazza del Duomo into heat traps during the afternoon. The Guardian's report does not single out Florence, but the red alert's application to all 27 major cities means the city's museums, churches and outdoor piazzas are now operating under the same extreme conditions that have already reshaped tourism patterns elsewhere in Italy this summer.

The heatwave has already prompted experts to urge night-time visits to major attractions, a measure that is now more urgent in Florence, where daytime temperatures make queuing outside the Accademia or the Uffizi a health risk. The BBC's heatwave guidance, published this week, recommends shifting sightseeing to the cooler hours of the early morning or evening, and seeking air-conditioned refuge in supermarkets and shopping centres during the peak of the day. For a city whose economy depends on the daytime flow of visitors through its monuments, that advice represents a significant challenge to the traditional tourist itinerary.

The red alert also puts pressure on the city's emergency services and on the municipal authorities responsible for the safety of both residents and the millions of visitors who pass through the centre each August. The Guardian's report highlights that the heatwave is the fourth of the summer, a pattern that climate scientists have linked to the broader warming trend affecting the Mediterranean basin. For Tuscany, whose image abroad is inseparable from its sun-drenched hills and Renaissance piazzas, the heatwave is a reminder that the postcard idyll is increasingly a climate stress test.