As tornadoes ripped through the South, more than a foot of snow was dumped over parts of the Midwest, making for a post-Christmas travel nightmare. NBC's Mike Seidel reports.

A wicked winter storm was sweeping east across the United States Wednesday, creating a post-holiday travel nightmare with more than a foot of snow in some places and thousands of flights canceled or delayed.

"Blizzard warnings stretch for 730 continuous miles due to Winter Storm Euclid," The Weather Channel’s Tom Niziol reported.

The white-out came a day after a Christmas storm unleashed heavy snow, deadly winds and even some tornadoes on the nation’s midsection, killing at least three people.

As millions of Americans braced for snow, rain, ice or more twisters, nearly 2,000 flights had been canceled and 10,000 were delayed, many at Dallas/Fort Worth, Philadelphia International, and Cleveland's Hopkins International, according to the travel website FllightStats.com. American Airlines had to cancel 500 flights, while Delta scrapped 200.

Read more at The Weather Channel

The forecast called for heavy snow from Indiana to New York and by mid-afternoon it was piling up: The National Weather Service reported 14.5 inches in Marion, Ill.; 11.8 inches in Bloomfield, Ind.; 9 inches in Brookville, Ohio; 7 inches in Bardwell, Ky.; and Frostburg, Md. Up to 3 inches of rain had fallen in North and South Carolina.

The National Weather Service said Wednesday night that spotters had reported up to a foot of snow in some Pennsylvania counties. Forecasters predicted 10 to 12 inches of snow in western and central Massachusetts.

The system was expected to taper off into a mix of rain and snow closer to the coast, where little or no accumulation was expected in such cities as Philadelphia, Boston and New York.

The storm left freezing temperatures in its aftermath, and forecasters also said parts of the Southeast from Virginia to Florida would see severe thunderstorms.

After the storm socked little Albion, Ill., with 18 inches of snow, city worker Renee Galen’s SUV got stuck and she got to her office the only way she could.

On one of the busiest travel days of the year, bad weather has forced airlines to cancel or delay flights. NBC's Katy Tur reports.

"One of the city guys came by with a snowplow and I flagged him down and rode to work with him," Galen told NBC News.

"I had to get to work because today was the last day to file for city elections. Believe it or not, I’ve had three people come in to file."

In Indianapolis, seven inches of snow fell in three hours Wednesday morning, bringing post-Christmas shopping to a halt, the Indianapolis Star reported.

Stephen Canter, 44, ventured out before 8 a.m., and the roads were thick with snow when he headed back 30 minutes later.

"By the time I got home, the street was covered," he told the newspaper. "I don't remember snow like this since Valentine's Day of 2007."

Indiana State Police received 100 calls of crashes or cars sliding off roads before noon and warned motorists that if they got into trouble it could take a while to get them help, NBC affiliate WTHR.com reported.

Cars and several 18-wheelers were stuck in the ice along 1-70, and the snow fell faster than crews could clear the roads.

"The biggest problem is the blowing. We got some high winds and the roads are really beginning to drift bad," Ron Sharp with Wayne County Emergency Management told the station.

Parts of New York, Ohio and Pennsylvania are also forecast to get hit with more than a foot of snow, and New England could get up to a foot.

The blizzard warning in Ohio prompted United Airlines to cancel at least 60 percent of their flights at Cleveland Hopkins Airport beginning at noon on Wednesday, according to NBC affiliate WKYC.com. About 1,000 people spent the night on cots at Dallas/Fort Worth after their Tuesday night and Wednesday morning flights were scrapped.

Hundreds of flights delayed, canceled as holiday storms travel across country

With Rochester, N.Y., slated to get up to a foot of snow, hordes of worried residents descended on the hardware stores.

“Un-freaking-believable! We’ve sold 225 shovels since 9 o’clock this morning,” said Tom Green, owner of Mayer Paint and Hardware. “Rock salt – I couldn’t tell you how many thousands of pounds I’ve sold today. People are very concerned.”

Green noted that snowstorms are hardly rare in Rochester.

“But this is the first big one,” he said. “And it’s happening at Christmas.”

The weather system, which started over the weekend, wreaked havoc on Christmas. It knocked out power to tens of thousands of people and was blamed for at least five deaths.

In Enola, Ark., two toddlers were killed when a car lost control on an ice-slicked highway and spun into oncoming traffic, state police said.

Wind-toppled trees killed a pickup truck driver near Houston, Texas, and a 53-year-old man in north Louisiana. NBC affiliate KJRH reported that a 28-year-old woman was killed in a crash on a snowy highway near Fairview, Okla.

Christmas Day tornadoes –- the preliminary count was at least 21, according to the Weather Channel -- battered Southern states. And Little Rock, Ark., didn’t just have a rare white Christmas –- it had its snowiest day ever, with nine inches on the ground.

The storms contributed to a 21-vehicle pile-up Tuesday that shut down a major highway in Oklahoma City, as well as tens of thousands of power outages. Emergency service provider MedStar told NBCDFW.com it responded to 71 crashes in the Fort Worth area between 5 p.m. and 9:50 p.m. Tuesday evening.

As it tracked east, authorities were taking the storm seriously.

In Indianapolis, Mayor Greg Ballard ordered "non-essential" workers to stay home and off roads. Cleveland asked businesses to send workers home by 1:30 p.m., NBC affiliate WKYC.com reported. Homeowners in coastal Long Island, ravaged by Superstorm Sandy in October, were told to take precautions to prevent flooding with seas expected to peak at 15 feet, NBCNewYork.com reported.

By the time it leaves the New England coast Friday, the storm will have left snow from coast to coast –- and there could be another wallop coming soon.

Weather Channel meteorologist Guy Walton said a weather pattern with the potential to become Winter Storm Freyr is poised to enter the West Coast on Wednesday and move through the Rockies on Thursday. It could then head for the lower Mississippi Valley, then the Southeast and hit the Northeast on Sunday.

Read more at weather.com

The Weather Channel's Jim Cantore and The Associated Press contributed to this report.

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