Large areas of Tuscany have been hit by flooding, leaving six people dead and several others missing, after heavy winds and rain buffeted central Italy.
Cars were swept away as the River Bisenzio flooded and people climbed on roofs to escape the deluge.
Hospitals were flooded, people in cars were trapped in underpasses and the west coast was lashed by high waves.
The extreme conditions are directly linked to Storm Ciarán which has caused more than 13 deaths in Western Europe.
Winds of 207km/h (129 mph) were recorded earlier on the north-west coast of France, as the storm also lashed southern England, Belgium, the Netherlands and Germany, as well as the Atlantic coast of Spain and Portugal.
Power lines went down and transport was severely disrupted. A five-year-old child was one of two people killed in Belgium by falling trees. Residents had to be evacuated from their homes on the Channel Island of Jersey.
A cold front of severe weather reached Tuscany on Thursday night, as winds reached 140km/h.
Regional governor Eugenio Giani described the heavy rain as "unprecedented in the past 100 years and, after a cabinet meeting, Prime Minister Giorgia Meloni declared a state of emergency for the worst-hit areas of Tuscany.
Livorno and Marina di Pisa on the coast and towns around Florence were among the worst affected areas, with the streets of Prato looking more like canals and nearby Seano resembling an island.
In Montemurlo, officials said on Friday that 200mm (7.8in) of rain had fallen since Thursday afternoon and the Bisenzio river burst its banks in two places.
An 85-year-old man was found dead on the ground floor of his flooded home. Rescuers believe he had been unable to climb the stairs to safety.
The governor of Tuscany shared a video showing cars being swept away by floodwater and appealed for people to go to upper floors.
Close to the river, in Campi Bisenzio, people climbed on to their roofs to get to safety and about 100 staff and customers sought refuge in a shopping centre.
A man and his wife were found dead after his car overturned in floodwater in Vinci, to the west of Florence. There had been fears that the River Arno would flood in Florence but the emergency appeared to have subsided by mid-morning.
The mayor of Prato, Matteo Biffoni, described overnight events as a "blow to the stomach". Floods left entire areas submerged and the ground floor of the town's Santo Stefano hospital was partially flooded.
The west coast was lashed by waves reaching 3.5m (11ft 5in), and Milan was hit by flooding for a second time this week, three days after the River Seveso burst its banks.
The storm also caused damage in the north-eastern region of Veneto, where one person was missing and Governor Luca Zaia said 160mm of rain had fallen in 24 hours.
Further east, there were red weather alerts in Slovenia and Croatia. Forecasters warned of high winds, hail and thunderstorms and authorities in Slovenia warned of one of the strongest cyclones in the past 10 years.