New Delhi, June 25 -- Much of western Europe baked under a "heat dome" Wednesday as temperatures soared toward 40 degrees Celsius (104 Fahrenheit) in places, and weather agencies warned that the extreme conditions could endanger lives across countries, many of which have limited air conditioning.

France recorded its hottest-ever day for the second day running. The Meteo France weather agency said the country's national thermal indicator - an average of temperatures measured at 30 weather stations - hit a new record of 30 C (86 F), the latest in a series of never-before-registered highs. The mercury surpassed 40 C (104 F) in some locations, including in Paris.

The French weather agency put three-quarters of the country under a red alert ...