According to the service's latest data, there is “no danger for German airports until the coming night at midnight,” spokesperson for the DWD air traffic centre Sabine Bork told news agency DPA.
At that point the problem will likely continue to diminish thanks to favourable weather patterns, she added.
“We'll get a southwesterly air stream over Iceland,” she said. “That means that the ash cloud isn't gone, it just won't be over central Europe and will instead be blown somewhere over the North Sea.”
Over the weekend European air traffic – particularly in the UK, the Netherlands and Belgium – was crippled once again by ash spewing from the Eyjafjallajökul volcano. On Monday morning most British airports were allowed to reopen, but the Amsterdam airport remained closed until 2 pm. Belgium's Ostende airport was also expected to stay closed until afternoon.
The closures were still felt in Germany, though. Airlines were forced to cancel 12 flights out of Hamburg to the affected cities of Amsterdam, Rotterdam and London, a spokeswoman said. Meanwhile flights to Dublin, Edinburgh, London and Nottingham were cancelled at Berlin's Schönefeld and Tegel airports.
Twelve long-haul flights were also rerouted to the Frankfurt Airport when they were not allowed to land at closed airports.
Volcanic ash already hindered European air traffic for five days in April, closing hundreds of airports across the continent and causing thousands of flight cancellations.
Carriers have criticised authorities for the ban, saying the lack of standards exaggerated fears, costing the industry more than a billion dollars in lost sales alone, according to an estimate by the International Air Transport Association (IATA).