Scorching temperatures across Europe forced the closure of the Acropolis in Athens for a second day as officials warned of even hotter weather next week.

In cities, those venturing out at all doused themselves in fountains while others sought out pools, the sea or shade in hopes of relief from the heat wave caused by Cerberus. The high-pressure anticyclone coming from the south was named after the three-headed dog in ancient Greek mythology who guarded the gates to the underworld.

Fifteen cities in Italy, most of them in the country’s centre and south, were under heat advisories on Saturday signalling a high level of risk for older adults, the infirm, infants and other vulnerable people. Temperatures remained in the mid-30C across much of the Italian peninsula but were expected to reach between 38C and 40C in Sardinia, Sicily and Puglia.

The cities under alerts included the high-tourism destinations of Bologna, Florence and Rome. The capital hit a high of 35C on Saturday and was expected to see temperatures soar to 42C on Tuesday.

In Athens, where the temperature was forecast to reach 41C, officials decided to keep the sun-baked Acropolis monument closed from noon to 5.30pm as they did on Friday.

Temperatures were milder in Spain’s Canary Islands, but a wildfire on the island of La Palma caused a preventive evacuation of some 500 people.

In Turkey, coastal cities in the south and southwest reached the high 30Cs and low 40Cs. The tourism hot spot of Antalya saw a high of 44C.

In the northwestern cities of Edirne, Kırklareli and Tekirdag, 48 people were taken to emergency rooms with symptoms of heat stroke in the past two days, the state-run Anadolu Agency reported.

The heatwave also was taking its toll on water levels in Istanbul, Turkey’s largest city. The main water supply at the Omerli Dam reservoir, already at 41 per cent capacity due to low rainfall, was losing 17,000 tonnes of water an hour during the early afternoon, Levent Kurnaz of Bosphorus University’s Center for Climate Change and Policy Studies said.

European countries father north also sweltered on Saturday.

In Germany, the highest temperatures of the year so far were recorded in Bavaria.

The town of Mohrendorf-Kleinseebach in Erlangen-Hochstadt recorded a temperature of 38.8C, a German Meteorological Service (DWD) meteorologist said based on preliminary data.

Other regions reported similar heat levels, such as Kitzingen, also in northern Bavaria, where the temperature was 37.8C, while in Dresden-Strehlen hit 37.3C.

High readings were also reported in Baden-Wurttemberg, where Notzingen in Esslingen reached 37.3C and Stuttgart-Echterdingen hit 37C.

Authorities in Poland warned older adults in particular to stay indoors or in the shade and well-hydrated as temperatures reached 35C.

In downtown Warsaw, and in other cities, makeshift hose fountains were arranged to let people and their pets cool off. Police issued warnings about not leaving children or pets unattended inside cars.

with DPA