In the southern city of Stuttgart, about a thousand airline passengers were stranded overnight after 70 flights were cancelled because of heavy snow, the airport said.

In Britain, the first snow of winter disrupted road and rail travel in southeast England.

Commuters faced severe delays on many routes into London. Southeastern, a train company serving the region, said it expected delays to continue during the afternoon and said its Web site crashed from a flood of passenger queries.

Britain's Met Office said heavier snowfalls were expected in parts of the southeast on Thursday and Friday.

Temperatures dipped to minus 10 Celsius (14 Fahrenheit) in parts of France.

About 5,000 vehicles were stranded when the A6 motorway that runs through eastern France was blocked by snow and 200 police officers and firefighters were sent to help stranded motorists.

Power was cut off to about 85,000 homes in central France and train travel was disrupted.

AVALANCHE WARNING

In Austria's Carinthia province, 12,000 homes lost electricity when heavy snow brought trees down on power lines and officials issued an avalanche warning for nearby Alpine areas.

A blizzard deposited more than a metre (three feet) of snow within hours, stranding hundreds of vehicles.

The cold weather is expected to continue for the rest of the week, bringing some relief to Europe's ski resorts which have been struggling because of a lack of snow.

Europe has been experiencing one of its warmest winters on record, raising concerns about climate change, and experts warned a return to winter conditions could threaten wildlife.

Rare bird populations in Romania's Danube Delta have begun nesting earlier than usual because of the warm weather. Meteorologists expect temperatures to drop below zero in the coming days, threatening colonies of Dalmatian pelicans, pygmy cormorants and spoonbills in the vast marshlands, one of Europe's most biodiverse regions and lying on a migratory route.

"Some species which were supposed to come at the end of February, are already here," Dan Hulea, president of the Romanian Ornithological Organisation, said. "If cold weather persists for more than 10 days, it will have a serious effect on the population."

Zoo animals in Moscow have started mating early this year because of the warmest Russian winter for a generation.