Venice joins red alert as fourth heatwave grips Italy

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, the Guardian reported on Wednesday. The red alert comes as temperatures in some areas edge close to 40C, according to the newspaper's Rome correspondent.

For Venice, the alert adds a new layer of strain to a city already contending with record tourist numbers and the environmental pressures of the lagoon. The red warning, which applies to cities including the Veneto capital, signals extreme conditions that pose health risks particularly to the elderly and vulnerable residents who remain in the historic centre.

The heatwave arrives as the city's narrow stone streets and sun-baked piazzas trap warmth well into the evening, offering little respite to those without air conditioning in centuries-old buildings. Foreign visitors accustomed to cooler northern summers face a demanding urban environment where water fountains and shaded porticoes become essential survival infrastructure.

The Guardian's report noted that the red alert — the highest level in Italy's three-tier heat warning system — would be in effect across all major urban centres from Trieste to Palermo. The newspaper described the measure as a response to the fourth heatwave of a summer that has repeatedly tested the country's infrastructure and public health systems.

The BBC, in a separate guide published this week, quoted experts on how to make the most of Italy during the latest heatwave, with advice ranging from seeking air-conditioned supermarkets to taking advantage of night-time tours. That guidance carries particular resonance in Venice, where daytime temperatures in the cramped alleyways of the Castello and Cannaregio districts can feel considerably higher than official readings taken at the airport or lagoon stations.

For the Veneto region, the heat compounds longer-term climate pressures that international science coverage has linked to the lagoon's future. Warmer air temperatures accelerate the evaporation of shallow lagoon waters and increase the frequency of intense summer storms, while the urban heat island effect makes the historic centre markedly warmer than the surrounding mainland. The red alert thus reads as both an immediate public health warning and a reminder of the environmental fragility that heritage bodies have repeatedly flagged.

The practical consequences for Venice's tourism economy are significant. Day-trippers arriving by train or cruise ship face heat exhaustion risks in open squares like San Marco, where shade is scarce and reflective stone amplifies the sun's intensity. Local authorities have in past heatwaves urged visitors to adjust their schedules, but the sheer volume of arrivals — a recurring theme in foreign coverage of the city — limits how effectively such advice can be communicated or enforced.

The Guardian's report did not specify how long the red alert would remain in place, but noted it came as the fourth heatwave of the summer intensified. With August traditionally the peak month for both tourism and heat in Venice, the warning is likely to shape the experience of the hundreds of thousands of visitors expected in the coming weeks, even as the city's permanent population continues its long decline.