Also on Thursday morning, police and fire departments warned of the danger of black ice in the north and east of the country. While the south of Germany could expect warmer temperatures, dangerous conditions would persist further north.
ADAC spokesman Andreas Hölzel said the day before Christmas Eve would be “the worst day” for driving, with “incredible amounts of traffic and many traffic jams” as people hit the roads for skiing holidays or to visit relatives.
The wave of travellers would be hampered by the “chaos and disaster” of recent heavy snow falls, which have caused havoc on the roads along with every other form of transport.
The German Weather Service has forecast snow in the north and west of the country, and rain in the south, on Thursday. Temperatures will be considerably higher than they have in recent days, hitting as much as 10 degrees Celsius in parts of the south. Isolated snow falls will continue overnight in the north. Some snow can also be expected on Friday in the northwest.
The A24 motorway between Berlin and Hamburg had ground to halt early Thursday morning because of icy conditions, police in Potsdam said. The motorway had to be closed near the exit to Neuruppin, northwest of Berlin, because of an accident in which two people – including a police officer – were injured.
The A7 south of Göttingen had to be partially closed due to several accidents caused by ice. Elsewhere in Lower Saxony, centimetre-thick ice formed on the A2 and A39.
"Whoever doesn't have to drive should leave their auto where it is," said a state traffic official.
Rain overnight across the state of Brandenburg had also frozen. Motorists were urged to exercise extreme caution.
Police in Kiel in the northern state of Schleswig-Holstein reported: “There were heavy snow drifts here overnight. Cars are stuck in places.”
There were also reports of sleet and rain hardening to ice in northern states such as Saxony-Anhalt, Mecklenburg-Western Pomerania.
As last week had shown, drivers should plan more time to reach their destinations, Hölzel said. ADAC advises people to listen closely and follow advice given on the radio.
With more snow forecast for parts of Germany over coming days, it was not impossible that motorists might find themselves stuck at motorway rest stops, Hölzel said, adding that in emergency cases it could be wiser for families simply to find a hotel along the way and wait a night.
Motorway service areas were on Wednesday already extremely busy. To cope with the flood of holidaymakers, they had stocked up on de-icing products for windscreens and ice scrapers.
The mass of traffic should have eased by Christmas Eve itself, Hölzel said. While cities might be frantic with last minute shoppers in the morning, the streets would be fairly quiet by Friday afternoon.
The firm Autobahn Tank & Rast will keep its 370 rest facilities open 24 hours a day right through Christmas.