The extreme weather has pushed temperatures above 40 degrees Celsius (104 Fahrenheit) in several countries, prompting health warnings for millions of people.

Across Europe, authorities are grappling with the consequences of extreme heat: health alerts for millions in Italy, record temperatures in Austria, drought-related disruptions to energy and shipping in Central Europe, and wildfires stretching from France to the Balkans.

Scientists and officials warn that such events are becoming more frequent and intense as the climate warms.

Climate change drives more extreme summers

From the Mediterranean to Central Europe, prolonged heat, drought and wildfire conditions are increasingly becoming defining features of summer. The current heat wave has exposed vulnerabilities in public health systems, power generation, transportation networks and tourism infrastructure, forcing governments and businesses to adapt to more frequent periods of extreme weather.

Italy’s Health Ministry placed all 27 cities monitored under its national heat surveillance system on red alert Thursday — the first time this year the entire network has been under the highest warning level simultaneously.

The alerts stretch from Trieste in the northeast to Palermo in Sicily and signal a health risk for the entire population, not only vulnerable groups such as older adults and people with chronic illnesses.

Authorities urged residents and tourists to avoid direct sunlight during the hottest hours of the day, remain indoors where possible and drink plenty of water as temperatures in some areas approached 40 C (104 F).

The heat has also forced adjustments at major tourist attractions. The ministries of tourism and culture extended evening opening hours at landmarks including Rome’s Colosseum and Pantheon.

Cooling mist fans have been installed at the Colosseum’s entrances and additional medical stations have been made available.

Austria breaks national temperature record

The most intense temperatures were recorded in Austria, where the mercury reached 41.2 C (106.2 F) on Wednesday in the village of Bad Deutsch-Altenburg near the Slovak border, according to GeoSphere Austria. It was the highest temperature ever recorded in the country.

Austria is also facing severe drought. Rainfall from Jan. 1 through June 30 was 27% below the long-term average nationwide, while some eastern regions received only half their normal precipitation.

Climatologist Alexander Orlik said some parts of the country had not experienced such dry conditions since 1885.

Hungary cuts power use as drought hits nuclear plant

In Hungary, prolonged drought and record-low water levels on the Danube River have severely affected the country’s only nuclear power plant, which relies on river water to cool its reactors.

Plant operators have reduced output to about 10% of normal production, prompting the government to introduce emergency conservation measures as a record-breaking heat wave grips the country.

Authorities have asked major industrial users and households to cut electricity consumption, particularly during peak demand hours between 5 p.m. and 10 p.m. Freight trains have been barred from operating during those hours, while decorative lighting on landmarks in Budapest has been switched off.

Several major companies, including energy company Mol, pharmaceutical maker Gedeon Richter and automakers Suzuki, Mercedes-Benz, Audi and BMW have announced plans to curb electricity use.

The government also canceled parliamentary sessions this week in an effort to conserve power.

The heat wave has shattered temperature records across the country. On Wednesday night, Budapest recorded its warmest overnight low temperature on record, with temperatures falling only to 28 degrees Celsius (82 degrees Fahrenheit), underscoring the persistence of the extreme heat.

Germany worries about shrinking rivers

Germany faced growing concerns over the impact of drought on transportation and industry as water levels on the Rhine and other rivers continued to fall.

Transport Minister Steffen Bilger met affected organizations Thursday and warned that low water levels posed major challenges for inland waterway shipping, industry and the broader logistics chain.

Environmental group BUND urged authorities to focus not only on the economic impacts but also on making rivers more resilient to climate change by retaining more water in landscapes and reducing withdrawals during periods of drought.

France remains on high wildfire alert

In southeastern France, firefighters maintained a large presence in the Var region after authorities said a major wildfire there was no longer spreading but remained capable of reigniting.

The blaze, which began July 20, has burned more than 60 square kilometers (23 square miles), making it the largest recorded in the region in recent decades.

Authorities warned that strong winds and extremely dry conditions left southeastern France at very high risk for additional wildfires.

Balkans battle fires and drought

The heat wave reached its peak across the Balkans on Thursday as temperatures neared 40 C (104 F) and authorities battled drought and wildfires.

In Serbia, firefighters struggled to contain several blazes after days of dry weather. One major fire burned through pine forests west of Belgrade, while another spread near the central town of Kraljevo, where difficult terrain complicated firefighting efforts.

In neighboring Croatia, tourists in Dubrovnik sought refuge in shade and avoided beaches during the hottest hours of the day as temperatures soared along the Adriatic coast.

———

Associated Press journalists Sylvie Corbet in Paris, Jovana Gec in Belgrade, Serbia and Karel Janicek in Prague contributed to this report.