A tourist protects herself from the sun under an umbrella in front of the Louvre Pyramid, designed by Chinese-US architect Ieoh Ming Pei in Paris on June 23, 2026, as France experiences a heatwave.Dimitar Dilkoff | Afp | Getty ImagesA record-breaking European heat wave has caused a major power outage in France, as several countries issue red alerts across large swaths of their territory.A heat-related incident left around 68,000 homes without electricity in western France, according to the prefecture in the coastal department of Finistere.The outage, which started on Tuesday evening and was related to a transformer in the town of Ergué-Gabéric, was not expected to be fully restored until the end of Wednesday at the earliest."Priority is being given to restoring power to healthcare facilities and critical sites. Nursing homes where power has not yet been restored to the grid will be provided with generators," the operator said in a statement.Data from French utility EDF, meanwhile, showed that the country's nuclear output nationwide was reduced by 4.1 gigawatts on Wednesday as high temperatures reduced access to cooling water, according to Reuters. CNBC has contacted EDF and is awaiting a response.It comes as a fresh bout of record-breaking heat disrupts school and transportation schedules in countries across the region.An empty street in Toulouse, France, on June 22, 2026. France experiences its second heatwave of the year. MeteoFrance reports that this day is expected to be one of the hottest on record.Alain Pitton | Nurphoto | Getty ImagesFrance on Tuesday recorded its hottest day ever on a national scale, according to the Meteo France weather service.The mercury notched 44.3 degrees Celsius (111.74 degrees Fahrenheit) in Pissos in southwestern France, Meteo France said, while many cities experienced "unprecedented" values regardless of the month, including 42.1 degrees Celsius in the port city of Bordeaux.Temperatures also hit a record of 29.8 degrees Celsius at France's national thermal indicator, which represents an average of temperatures measured at 30 weather stations.At least 40 people were reported to have drowned in France while swimming in unsupervised areas to seek relief from the heat over the last few days.Elsewhere, the U.K. closed more than 1,000 schools across England and Wales as a rare red weather warning came into effect on Wednesday morning. Similar warnings were also put in place in Spain, Italy, Germany and Switzerland, among other countries. In the U.K., the red warning caters for an exceptional spell of hot and humid weather, which carries the potential for adverse health effects population wide and means substantial changes in daily routines will be required. Europe's latest heat wave is its second so-called heat dome in just two months and comes as scientists warn climate change is making extreme weather events more frequent and intense.Europe is warming faster than any other continent, at twice the speed of the global average since the 1980s, according to the European Union's Copernicus Climate Change Service.