Some 40,000 migrants could arrive in Germany over the next two days - double the number who entered the country last weekend, authorities said on Saturday.
Most are expected to arrive in the southern city of Munich but there are concerns about whether the region can cope with another large influx, BBC reported.
Many migrants received a warm welcome at Munich railway station last weekend, and thousands have continued to arrive in Germany throughout the week.
The mayor of Munich, Dieter Reiter, has made an urgent call for other German regions to do more to process and accommodate the new arrivals.
He described as "scandalous" the failure of other regions to provide more accommodation.
Reports suggest the government is considering new temporary powers to take control of unoccupied rental property so it can accommodate migrants.
A large processing hub is planned for northern Germany on the Luneburg Heath in Lower Saxony.
Trains would take migrants there directly from Austria.
Meanwhile, protests in support of migrants are expected across Europe later on Saturday.
