Heavy rain, giant hailstones and gale-force winds lashed parts of Germany, Switzerland and France on Monday and Tuesday, causing widespread flooding and tearing off part of the roof of an opera house.

Several road tunnels were flooded and rail services were completely suspended in and around the German city of Stuttgart on Monday night, according to police and rail operator Deutsche Bahn.

Video footage showed rivers of water gushing down streets and car windscreens shattered by huge hailstones.

Brutal summer storms tore off part of the roof at the opera house in Stuttgart, southern Germany
Brutal summer storms tore off part of the roof at the opera house in Stuttgart, southern Germany dpa / Christoph Schmidt

Emergency services across the southern states of Rheinland-Palatinate and Baden-Wuerttemberg reported hundreds of calls to deal with flooded cellars, fallen trees, landslides and stranded drivers.

At around 8:30 pm, a heavy gust of wind tore off part of the roof of the Stuttgart Opera while around 250 people were still inside following a song recital.

A large section of copper cladding landed in the opera house gardens, managing director Oliver Hendriks told AFP.

No one was injured but staff were still assessing the damage caused by several thousand litres of rainwater entering the opera house, he said.

Sections of roofing landed in front of the Stuttgart Opera House
Sections of roofing landed in front of the Stuttgart Opera House dpa / Christoph Schmidt

In Nottwill, in the Swiss canton of Lucerne, the Swiss news agency ATS reported giant hailstones up to seven centimetres wide.

In the canton of Fribourg, the police and fire brigade were called 300 times, including to rescue a class of 16 children and two adults caught in the hail.

Six of the children and one adult were taken to hospital.

At least five people were injured in the German-speaking Swiss cantons, including a cyclist who suffered head injuries from hailstones, according to ATS.

In France, several dozen centimetres of hail fell in the southeastern Vosges region on Tuesday, prompting the unseasonal use of snow shovels and snowploughs.

The Meteo France weather service issued a storm warning for the whole of the northeast of the country.

Poor conditions looked set to continue into Tuesday evening in Germany, with forecasters warning of further thunderstorms and heavy rain in the north and east of the country.