Malmö, southern Sweden, received 20 millimetres of rain in under an hour on Sunday morning. One area near the town of Falsterbo rececived as much as 43 millimetres of rain during the night and early morning.
"We usually issue a warning if there will be 35 millimetres within 12 hours," Lovisa Andersson, meteorologist at Sweden's weather agency SMHI, stated.
A Danish weather agency, DMI, issued a warning for extreme rains in the Copenhagen area at around 10pm on Saturday night. There was no such warning on the Swedish side.
"It may have rained a lot over Malmö locally, but for a warning the rains have to cover a large surface area," Andersson told regional paper Sydsvenskan.
The agency has now issued a class 1 warning for all of Skåne, saying that up to 50 additional millimetres may pour down on Sunday.
Police have received more than one hundred SOS calls, and over 500 households have been left without power. Emergency services have had to evacuate buses filled up to the windows with water.
"Some cars are filled with water up to the roof. A man called us at 6:30am and said that he had been forced to swim from his car," Stephan Söderholm, Skåne police spokesman, said in a statement. "We have serious problems on the roads in western Skåne right now."
Highways 585 and E6 have been partially blocked due to flooding. Police have stated that people should stay home and not venture into traffic.
Police also reported that several manhole covers on the streets of Malmö had been lifted by the waters, as there was simply too much water to run off the streets.