France has triggered a rare red alert over the latest heatwave to hit the country as temperatures are expected to reach in 42°C on Wednesday in the southern Rhone valley.
"A lasting and intense heatwave for the period has settled over the country," officials said in a statement on Monday.
The departments of Rhone, Drome, Ardeche and Haute-Loire were under the highest alert effective at 4pm local time, with peaks expected in the south-west and the Rhone valley.
It was the sixth time Meteo France has triggered the red alert – part of the government's scheme to protect the population during periods of extreme weather – and the first this year.
The latest wave of hot weather has been caused by a so-called heat dome, a meteorological event characterised by a persistent high-pressure system that acts as a barrier, trapping warm air on the ground.
South and south-eastern France are the regions most affected by extreme temperatures, while the north and north-west have temperatures considered normal for this time of year.
This regional disparity is reflected in a list of France's 70 hottest cities compiled by daily newspaper Le Figaro.
Cities in the south-east, such as Annecy, Lyon and Saint-Etienne, are expected to experience the biggest temperature increase.
Based on climate scenarios provided by French laboratories, the newspaper calculated the number of unusually hot days expected throughout June, July and August between 2041 and 2070.
An unusually hot day is when the temperatures is at least 5°C higher than the 1975-2006 average.
A number of other south-eastern and eastern cities, such as Avignon, Valence and Dijon, are believed by climate experts to be similarly affected.
They are all expected to experience on average 16 unusually hot days a year.
Paris is ranked 41st in the list, with a predicted 10 unusually hot days.
Northern cities are set to be least affected by temperature increases in France, with only four days of unusually hot weather a year expected in the port city of Calais.
Cities in the western region of Brittany, including Brest, Quimper and Lorient, are scheduled to experience between six and eight unusually hot days a year.
Meanwhile, about 260 firefighters were battling a fire near the village of Chanousse in the foothills of the Alps in south-east France, the Association for the Prevention and Reporting of Forest Fires reported on Monday.
Flames have consumed about 120 hectares of woodland, local authorities said.
Power company EDF has extended a power cut at its 1.3 gigawatt Golfech 2 nuclear reactor in south-western France on Monday because river water used to cool the reactor had surpassed maximum temperatures due to excessively hot weather.
A restart has been delayed until Friday.
The heatwave extends beyond France, with Spain and Greece blighted by new wildfires. In Spain’s Canary Islands, a blaze that police say was started deliberately last Tuesday on Tenerife continued to burn out of control, although the worst seemed to have passed. More than 12,000 people have been evacuated from their homes and about 13,400 hectares of pine forest and scrubland have burnt.
In Greece, authorities ordered the evacuation of two villages in the central Viotia region, about 100km north-west of Athens, after a forest fire broke out on Monday morning. The coastguard placed two patrol boats and several fishing boats and private vessels on standby in case an evacuation by sea was necessary.
Temperatures in Madrid expected to hover just below 40°C, more than 6°C above normal for the time of year, according to Maxar Technologies.
It has been a summer of extreme weather, from wildfires to flooding and violent storms across the Northern Hemisphere. The world’s hottest month ever was recorded in July and the extreme weather increases the intensity of such events.
Fires are still raging across parts of south-east Europe as dry, hot weather provides perfect conditions for blazes to ignite. A wildfire that began on Saturday morning in the Alexandroupolis in north-east Greece is still burning, according to authorities.