Severe winter weather prompted the cancellation of hundreds of flights on Wednesday at Frankfurt airport, Germany's busiest, as the country faced heavy snowfall and freezing rain.

A Frankfurt airport spokeswoman said 570 of 1,047 flights had been axed from the schedule by late morning as Germany's business capital prepared for dramatic weather conditions.

By early afternoon, all remaining departures were struck from the schedule due to the onset of freezing rain although landings were still possible, a spokesman said. It was not immediately clear how long the disruption would continue.

Munich airport also reported "significant restrictions in flight service" due to bad weather, with 250 of 650 scheduled flights cancelled.

Flag carrier Lufthansa advised passengers to confirm that their flights were still scheduled before setting off for airports.

Low pressure system Gertrud bearing down on southwestern and central Germany promised up to 40 centimetres of snow and treacherously icy road conditions, particularly in the state of Baden-Wuerttemberg.

State police there reported an "accumulation of accidents" on roads near Baden-Baden while national rail company Deutsche Bahn said it was slowing down its high-speed trains due to slick conditions.

It warned of delays and cancellations in its regional and long-distance network, particularly between the western cities of Cologne and Frankfurt.

Firefighters and other first responders in Rhineland-Palatinate in the southwest prepared for a rash of road accidents and other emergencies by calling up extra staff and vehicles. They urged motorists not to take to the roads unless absolutely necessary.

In large parts of Bavaria, Germany's biggest state, schools were shuttered in anticipation of dangerous winter conditions. (AFP)