Italy placed all of its major cities under the highest heat alert Thursday as a blistering heat wave gripped Europe, setting a national temperature record in Austria, fueling wildfires in France and disrupting energy and transport systems across the continent.

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

Sasa, an alert and floppy-eared mixed-breed puppy, did not return home when the remaining containment lines were lifted Wednesday in the wake of a wildfire that swept across mountains and coastal areas near Athens.

The pup was one of hundreds of pets and wild animals rescued by volunteers this week during the blaze, which prompted multiple evacuations.

Airline passengers know to expect possible flight delays when weather forecasts call for thunderstorms, heavy snow or strong wind. The omens are less obvious on a hot summer day with clear skies.

Yet extreme heat also disrupts flights and travel plans. On the hottest days, thinner air can make it harder for aircraft to get off the ground safely. Airlines may have to lighten the load by removing passengers or cargo, or carrying less fuel.

Fans fainting at a baseball park. Lions dying at a zoo. A woman taking shelter in a car found dead. A doctor advising people to eat dog meat to promote stamina.

The scenes caused by a record heat wave in Northeast Asia illustrate how extreme temperatures have gripped South Korea, North Korea and Japan.

Firefighters raced to exploit a break in high winds to strengthen containment lines on fires west of the Greek capital Tuesday ahead of stronger gusts and hotter temperatures in the coming days.

Several fires that burned through mountain communities and coastal areas west of Athens were brought under control overnight. Planes and helicopters dumped water inside the contained perimeters through the morning, dousing hot spots while the winds stayed calm.

Water levels on the Danube River, the second longest in Europe, have dropped so low because of drought that the hulks of dozens of World War II German battleships are emerging into view.

They are a curious distraction from the summer heat crisis. The Danube's record low water levels also have forced power plants to the brink of shutting down, and governments across Central and Eastern Europe are taking steps to conserve electricity.

Numerous governments across Central and Eastern Europe are taking steps to conserve electricity and avert an energy crisis as record low water levels on the Danube River have forced power plants to the brink of shutting down.

Persistent drought and successive extreme heat waves have deprived one of Europe's largest rivers of water, pushing the Danube's levels in Hungary's capital Budapest to around 10 centimeters (4 inches) on Monday, well below the previous all-time low of 33 centimeters (13 inches) set in 2018.

Climate change's fingerprints are all over the extreme fire weather that sparked this week's devastating wildfires in Spain and France and has spiked Southern Europe's burning the past eight years, two new studies conclude.

Human-caused climate change made the hot and dry conditions responsible for Spain's record-sized inferno 20 times more likely to happen, and it doubled the chances of extreme fire conditions for the flames in France, scientists at World Weather Attribution calculated in a rapid analysis Thursday, conducted while fires were still burning. Warming in the past 26 years has tripled the odds of the severe fire risk conditions in Spain and increased the chances in France 40%, the same report found.

Keepers at Prague Zoo used tons of ice on Thursday to give its animals some much-needed relief as yet another heat wave hit Europe.

Polar bears Aleut and Gregor wasted no time and were rolling in the beds of ice cubes after entering their outside enclosure.

From his vineyards in Bordeaux wine country, Edouard le Grix de la Salle can sometimes smell the burning forests far away. The smoke brings a whiff of hardship for the region's economic fortunes.

Wildfires that have burned an area four times the size of Paris and driven 220,000 people from homes and some of the region's tourist attractions promise to sting France's already squeezed economy.