Around 700 passengers were forced to wait hours overnight in five inter-city trains stuck between Berlin and Hannover overnight. The track became passable again on Friday morning, and semi-normal service was resumed.
But a spokesman for German rail operator Deutsche Bahn said the disruptions will continue throughout the day.
Local trains were severely affected by the weather, with services in a 50-kilometre radius around Hannover suspended until Friday morning.
Heavy snowfall has caused massive problems in the north-eastern state of Mecklenburg-Vorpommern. Snowdrifts reached over a metre in height in some parts of the state following 25 centimetres of fresh snow overnight.
Dozens of trees collapsed under the weight of the freezing snow, blocking traffic on interstate and local roads. Police reported that several vehicles had got stuck, but there were no serious accidents. There were also electricity blackouts in some areas of the state.
In the populous western state of North Rhine-Westphalia, meanwhile, some 1,734 road accidents were counted within 24 hours. Some 114 people were injured, 16 seriously.
One person was killed and several people injured in a huge multiple-car pile-up on the A9 motorway in the state of Saxony-Anhalt. Some 51 vehicles were involved, including four trucks, two small vans and 45 cars. The resulting blockage caused a 15-km tailback in the direction of Munich.
Chaotic weather conditions were also reported on the A1, A2 and A7 motorways.