At least 10 people have been killed in Germany and France, five on Thursday, as torrential rains and floods wreaked havoc in the region over the last few days.
Several people are missing as thousands are being forced to evacuate while numerous people are trapped in their homes or schools.
Rescuers are now using lifeboats down streets which better resemble muddy rivers.
The dead in Germany's Bavarian town of Simbach am Inn include three women from the same family—a mother, grandmother and daughter—who had been trapped in their house.
"The water was so quick that practically no residents had the time to run away," police spokesman Armin Angloher said.
Police said a man's body had also been found in a house in Simbach, while an 80-year-old woman was found dead in Julbach a few kilometres away. Her house had collapsed under the weight of the floodwaters.
The force of the water swept away the entire stock of a sawmill in the Germany's Bavarian town of Simbach am Inn, leaving huge stacks of splintered wood blocking the streets of the devastated town.
On one street, passers-by were greeted by the surreal sight of a car parked vertically against the wall of a house, pushed there by the floodwaters. Many other vehicles lay flipped over in roads blanketed by mud.
Four others are missing, a police spokesperson in Bavaria told AFP. "We fear the worst," he said, adding divers have been sent to search for the victims.
German Chancellor Angela Merkel told a press conference: "I am crying for the people who have lost their lives in these floods. I am by the side of families who have been plunged into this devastation."
The deaths bring the toll from the floods to nine in Germany, including four others were killed earlier this week in the southern of Baden-Wuerttemberg.
STATE OF EMERGENCY
President Francois Hollande declared a state of emergency in the worst affected areas and promised money to help local authorities deal with the flood damage.
An 86-year-old French woman was reported killed in the floods after her body was found in her inundated home south of Paris, but it now appears she died several days ago, police said.
In Paris, officials were putting up emergency flood barriers on Thursday along the swollen river Seine after days of torrential rain, including near the Louvre, home to priceless works of art, whose staff were told the venue was likely to close on Friday.
The move will allow staff to move works at risk of damage, according to the BBC.
The Seine rose above 5 metres (16 feet), forcing the SNCF rail operator to close an underground commuter line that runs along the river and is used by tourists to reach the Eiffel Tower and Notre-Dame Cathedral. The river reached a record high of 8.60 metres in 1910.
FRANCE, FLOODS AND STRIKES
Some towns in central France are suffering one of the worst floods in more than a century, with more than 5,000 people evacuated since the weekend.
Forecaster Meteo France described the situation as "exceptional, worse than the floods of 1910," when even central Paris was flooded.
Some 24,400 homes were without power in the Paris region and Loiret, utility provider Enedis. The floods forced the shutdown of one of the capital's main commuter train lines.
The torrential rains have also hit the French Open tennis tournament, washing out play earlier in the week, leaving players hoping to reach the finals facing a heavy schedule of matches.
In the town of Montargis, only the tops of cars could be seen peaking above the surface.
About 200 people had to spend the night in a gymnasium in Nemours south of Paris and Prime Minister Manuel Valls, visiting the flooded town's a crisis control centre, said at least 2,000 more people needed to be evacuated.
"The situation remains tense and difficult in several areas. We still have many concerns."
Sylvette Gounaud, a local shop worker, said she had seen nothing like this in 70 years of living in the town. "The centre of town is totally under water, all the shops are destroyed," she said.
Schools and roads have also been flooded in Austria in recent days, though the waters have now receded.
Forecasters in both Germany and France have warned of more torrential downpour in the next 24 hours.
The severe weather began at the weekend; lightning strikes left several children in Paris and western Germany fighting for their lives.
In Simbach, the waters had subsided largely subsided by noon on Thursday, leaving only the town's main artery still flooded.