London:
The snow was melting off London's streets, but Heathrow Airport told infuriated passengers it won't restore full service until Thursday -- five days after a five-inch (12-centimeter) snowfall turned hundreds of thousands of holiday plans into a nightmare of canceled flights and painful nights sleeping on terminal floors.
Traveller's anger boiled over into politics as Britain's prime minister offered to put troops on snow-clearing duty and Europe's top transport official threatened tougher regulation of airports unable to cope with wintry weather.
"It's pathetic -- you would think this is a Third World country," said 29-year-old Janice Phillips, who was trying to get back to Minneapolis. She sat next to her sleeping boyfriend, his head propped against a backpack, his mouth ajar. "All they've been talking about was this snow forecast. You would think the government could do a better job."
"It's not even snowing!" said 19-year-old Candie Sparks, who was trying to get back to Santa Fe, New Mexico. "It's crazy."
Days after a driving snowfall that ended Saturday after dumping five inches in an hour, the terminals at Heathrow were clogged Tuesday with passengers desperately looking at computer screens to see if they would be able to get to their destinations. So many people were sprawled on the floor that it was difficult to walk.
Some wore Santa hats decorated with vulgar signs making fun of their most un-merry Christmas.
Transportation experts said that after many years without heavy snowfall, underinvestment has left Heathrow and dozens of other airports across Britain and Ireland without enough equipment or personnel to cope with big storms.
"They have concluded they don't need snow clearance equipment, so we don't have the capability when bad weather comes in," aviation consultant Chris Yates said.
He said airport operators in Helsinki, Stockholm and other snowy climes have the equipment and manpower to clear runways within 30 minutes and to remove ice and snow from aircraft stands quickly, while Heathrow lags far behind.
This was evident in the days after Saturday's snowstorm, when airports in Frankfurt, Prague, Amsterdam and other major cities in mainland Europe bounced back more quickly than Heathrow, where the ice quickly hardened, making removal more difficult.
London's Gatwick was hit by less snow and recovered faster than the larger Heathrow. Its runway reopened and flights were operating Tuesday night.
European Union transportation commissioner Siim Kallas threatened tougher regulation if performance does not improve. "Better preparedness, in line with what is done in Northern Europe is not an optional extra, it must be planned for and with the necessary investment," he said.
Prime Minister David Cameron said his government had offered military assistance to the company that operates Heathrow, BAA Ltd., which thanked him but said it didn't need the help.
Still, even as the second of Heathrow's two runways reopened late Tuesday, officials said they needed "breathing space" to clear remaining snow, restart equipment and move planes and crews back into place. As a result, the airport would only operate about one-third of its normal flight schedule until 6 a.m. on Thursday.
Eurostar, the high-speed train that connects to mainland Europe through the Channel Tunnel, also could not cope, advising passengers throughout the day to cancel and stay home.
Outside London's Eurostar terminal, the line of travelers waiting for trains snaked several hundred yards (meters) down the street from the station.
Inside, puffy-eyed passengers shuffled across the cold concourse, watching anxiously as the line periodically spurted forward. One older man played Beethoven's "Ode to Joy" on his harmonica; the crowd livened up when he switched to the Swedish rock band Europe's heavy metal anthem "The Final Countdown."
By evening, Eurostar said it expected to operate a nearly normal schedule on Wednesday but said passengers who had missed previous trains would still not be able to travel.
Eurostar trains have been running with speed restrictions in both England and France as a precaution because of the snow.
Rail expert Christian Wolmar said Eurostar was being cautious after holiday-season breakdowns last year caused by powdery snow sucked into the engines of speeding trains. The entire Eurostar service was halted for three days when trains got stuck in the Channel Tunnel.
Wolmar said the real problem was bad management. "Eurostar ought to be ashamed of themselves," he said. "It would seem possible to put on extra trains, but they can't get the crews or they can't get the trains in place .... It's inexplicable."
The icy road conditions also forced many major businesses in the UK to stop taking online orders for pre-Christmas delivery. Weather experts warned of more extreme weather ahead.
The usual prevailing stream of warm, wet Gulf air is getting blocked and diverted midway across the Atlantic, they said -- allowing cold fronts from the Arctic and Eastern Europe to mount a rare prolonged invasion of Western Europe.
When those cold fronts pass over the relatively warm North Sea and Irish Sea, they turn into snow factories of rare power.
Many experts say global warming can lead, counterintuitively, to more powerful winter storms because of higher volumes of moisture in the air.
"The 1960s was a 5- to 10-year period of extreme weather, hot and cold. We could well be going into such a period and my advice would be prepare for it," said Sir David King, former chief scientific adviser to the British government, who is now director of the Smith School of Enterprise and the Environment at Oxford University.
"The risk to our economy is significant if this happens and we're not prepared."
In Ireland, intense, sustained snow has snarled traffic and shut down the country's major airport north of Dublin. Dublin Airport officials said the intensifying snowfall meant they couldn't keep runways free of ice.
Problems also persisted in Germany, where Frankfurt airport, continental Europe's second-largest hub, saw 550 cancellations out of a total of about 1,300 flights Tuesday because of bad weather conditions.