The record-breaking heatwave sweeping Europe could cause the ceiling of Notre Dame Cathedral to collapse, experts have warned.

Philippe Villeneuve, the chief architect of France's historic monuments, said the cathedral's stone walls are still saturated with water sprayed by firefighters during the blaze in April.

With record temperatures expected in Paris this week, Mr Villeneuve said the walls could dry too fast and the structure remains fragile.

Image: Specialists are working to stabilise the cathedral's structure

He added: "What I fear is that the joints or the masonry, as they dry, lose their cohesion... and all of sudden, the vault gives way."

Specialists are working to stabilise the cathedral's structure before reconstruction work begins.


European countries have been struggling with the effects of extreme heat, with temperatures passing 40C (104F) on Wednesday and more hot weather forecast.

For the second time this month, the continent is experiencing the effects of a high pressure system which is drawing hot air from the Sahara desert.

This air is trapped between colder stormy systems and is forming a "little heat dome" over Europe, according to Ryan Maue, a private meteorologist in the US.

The Netherlands recorded 39.3C (102.7F) at Eindhoven on Wednesday, while Belgium reached 38.9C (102F) at Kleine Brogel, both breaking national records set decades ago.

Image: In Germany, people crowded on to the beach at Zinnowitz in the Baltic Sea

Temperatures are expected to go even higher on Thursday.

England's South East and the French capital of Paris could see around 40C (104F).

In Germany, the temperature could break the country's record of 40.3C (104.5F) and in the Netherlands, salt has been spread on the roads - not to prevent the formation of ice but to cool the asphalt and stop it getting sticky.

In Spain, a large fire in Zaragoza province is almost under control but more blazes are expected as the temperature heads towards 41C (105.8F) on Thursday.

Image: Bottles of water have been given out to commuters in Paris

Belgian zookeepers have also been feeding tigers with chickens encased in giant ice cubes during the extreme heat.

In Italy, fire warnings have been issued for the island of Sardinia, where temperatures could top 40C (104F). Thirteen other cities have been put on the highest level of alert.

In France, where a 2003 heatwave killed 15,000 people, there have been announcements on the news and on public transport telling people to drink water and check in on elderly people.

Parts of the continent have not seen much rain recently, so droughts are being worsened by the hot weather, with wind and lightning also increasing the fire risk.

Image: There are also droughts in many parts of Europe and the heat is making these worse

But scientists say this could become the new norm.

Declan Finney, a research fellow at the University of Leeds, said: "With further climate change there could be a 50% chance of having hot summers in future.

"That's similar to saying that a normal summer in future will be as hot as our hottest summers to date."

Pennsylvania State University climate scientist Michael Mann said: "Either of the two European heatwaves this summer would have been remarkable in isolation.

"But now we are seeing multiple episodes of record heat in a given summer. By mid-century, we will simply call these episodes 'summer' - if we continue on this trajectory."