Thousands of German troops have been sent to help flood-hit regions as rising rivers threaten more cities, BBC reports.
Surging waters that have already caused extensive damage across central Europe are moving north and east along rivers including the Elbe and Danube.
German Chancellor Angela Merkel has visited areas already hit by the deluge and promised 100m euros (£78m; $130m) in emergency aid.
Meanwhile river levels in the Czech capital Prague have begun to fall.
Large areas of suburban Prague were flooded but metal barriers protecting the historic city centre held as the floods peaked and the high waters moved north towards Germany.
Around 4,000 German troops have been deployed in four states, the military said, reinforcing dykes with sandbags and providing help to thousands of people forced to leave their homes.
The latest cities to be hit include Meissen on the Elbe. Nearby Dresden is preparing for water levels 5m higher than normal.
Officials in Saxony – home to both Meissen and Dresden – have warned that rivers could rise even higher than in the record floods of 2002, when both cities were devastated.
Chancellor Merkel toured some of the worst-hit areas on Tuesday, flying over Bavaria, Saxony and Thuringia by helicopter.
In the stricken Bavarian city of Passau – where waters reached a level not seen in 500 years – she called the floods "an event of historic proportions" and promised 100m euros in emergency aid, half of it from the federal government
"I spoke to residents who are already busy with clean-up work and I am aware that it will take weeks. The damage and loss of income are a long-term problem and therefore our support will not dwindle," she said.
Across Europe at least 12 people have died as a result of the floods. As well as Germany and the Czech Republic, Austria, Switzerland, Poland, Slovakia and Hungary have been affected.
The Punch