France was hit hard, forcing hundreds of schools to tweak their timetables to cope. Forecasters warned of an "intense and long-lasting" heat wave that could see temperatures in Paris soar above 40C (104F) for the first time on a June day.

Across the continent, authorities were ramping up warnings of extreme weather. German forecasters said parts of the country needed to be on alert for thunderstorms, hail and heavy rain over the weekend.

Meteorologists confirmed that England and Wales had already experienced the hottest spring ever recorded, though temperatures in Britain were not expected to be as intense as those in continental Europe.

Scientists say human-driven climate change is amplifying such extremes, with heat waves, droughts and floods becoming more intense and frequent.

The current heat wave is already the second of the year for many, and means summer is kicking off for tens of millions of Western Europeans with another spell of extreme heat.

Britain, France, Spain, Switzerland and Germany have all raised alert levels for the coming days, as have some cities in northern and central Italy.