CHICAGO – A massive winter storm Thursday snarled holiday travel across the central United States as freezing rain and heavy snow caused traffic chaos and threatened to ground more flights.
"There's just a humongous storm moving across the center of the country, basically from the Canadian border to Texas and spreading from west Colorado to Illinois," said National Weather Service (NWS) spokesman Pat Slattery.
"Christmas travel is going to be very difficult."
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The northern parts of the storm were expected to drop up to two feet (61 centimetres) of snow while flood warnings were issued further south.
A powerful tornado late Wednesday on the storm's southern flank slammed the town of Longview in eastern Texas, ripping the roof off a house and toppling trees, the local KLTV station reported.
"We would recommend that people if at all possible postpone their travel plans just to be on the safe side," Slattery said in a telephone interview.
"This is not a storm to be messed with."
Freezing rain would make driving extremely dangerous -- especially after dark when the rain turns to ice -- and high winds would dramatically reduce visibility, Slattery warned.
"If they can wait a couple days, the snow will be there but it won't be blowing sideways anymore."
More than 260 flights were cancelled at Chicago airports Wednesday due to icy conditions and heavy, wet snow and sleet.
Train service was also interrupted for three hours at New York's Penn Station due to a power outage that disrupted travel from Washington to Niagara Falls on the Canadian border.
Teacher Elana Hiller managed to get home to Chicago from Minneapolis, but only after heading into the airport eight hours early to switch to a morning flight.
"The airports were crazy," she told AFP.
"The lineups at security were going all the way down from one end of the terminal to another."
United Airlines said it is doing its best to make sure people manage to get home for the holidays.
"We're trying to stay ahead of the storm rather than behind it," spokeswoman Sarah Massier said.
"We knew it's a holiday and it's very important for these customers to be home for the holidays."
The airline -- like most of its competitors -- automatically rebooks passengers on the next available flight following a cancellation and tries to get in touch by phone or e-mail to help people plan ahead.
But with flights already heavily booked for one of the busiest travel days of the year, painful delays and disappointment appear inevitable.
A NWS winter storm warning issued early Thursday for South Dakota, and echoed in alerts for neighboring states, said the event was a "life threatening system." It warned that "any travel from Wednesday night into Friday night will be treacherous."
The governor of South Dakota, Mike Rounds, who had declared a state of emergency before the storm's arrival, urging residents to stay off the roads.
"If you can't (leave before the storm hits) it's better to be safe than stranded somewhere. The best gift to give your loved ones is to be safe," he said.
It is the second major weather system to sweep the United States in recent days, after the massive snowstorm that slammed the eastern seaboard at the weekend. That first storm creating travel chaos and cut short sales on what were traditionally major shopping days ahead of Christmas.
The record-breaking blizzard closed train and bus service, paralyzed air traffic and left hundreds of thousands of residents without power.
A final Senate vote on landmark health care reform was pushed up to daybreak Thursday to give lawmakers and staff a chance to make it home for the holidays in the face of the massive Midwest storm.