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. A red alert means there is a higher chance of an emergency owing to the health risk posed by prolonged extreme temperatures to the entire population. Twenty-five cities were on red alert on Wednesday, with two more to be added on Thursday, the health ministry said. It is the first time this year that all 27 cities monitored by the health ministry’s heat surveillance system have been placed on maximum alert. The cities on red alert are: Turin, Bolzano, Milan, Genoa, Venice, Verona, Trieste, Bologna, Florence, Perugia, Rome, Naples, Ancona, Pescara, Bari, Campobasso, Reggio Calabria, Palermo and Cagliari as well as Catania, Messina, Brescia, Viterbo, Latina, Rieti, Frosinone and Civitavecchia.