Transcript for 'Bone-chilling' blast of arctic air lashing the Northeast
We begin with the arctic blast arriving for the holiday. The coldest Thanksgiving in years for 70 million Americans. Holiday travelers on an amtrak train out of ball Manny, new York, waiting for hours when their car separated from the rest of the train. Spectators bundled up to watch New York's Macy's parade. The coldest in the parade's history. That arctic blast chilling the entire region, setting a number of new record lows and tomorrow, another day of bitter cold. ABC's Sam champion with the big picture, starting us off here in New York City. Reporter: Tonight, a brutal blast of arctic air lashing the northeast. In some cases, 30 degrees colder than Normal. In Boston, an expected high of just 22 degrees. More than 100 years since its been this cold on this day. It is bone chilling out there, and the wind is not helping. Reporter: In Philadelphia, balloons in city's parade flying a shorter route than Normal because of the gusty arctic winds. Here in New York City, the coldest Macy's Thanksgiving day parade on record. Millions along the route battling wind chills feeling like between 5 and 15 degrees. Officials issuing an "Extreme cold weather alert" unusually early in the season, urging people to keep their skin covered to avoid frostbite. Lots of layers, it's necessary. You got to go shirt, sweatshirt, more sweatshirts, jacket, scarf, anything. Reporter: How many layers do you have on? A lot. I have like five pants and six shirts. Reporter: And just as that frigid cold swooped in Wednesday evening, a terrifying moment for the nearly 300 people onboard this amtrak train. I realized that we were no longer connected to the rest of the train. We're in trouble. Reporter: Two cars separating from the rest of the train outsiding a banny, New York. Brutal cold air rushing in. Another train taking passengers to their designations after about a two-hour delay. Sam joins us now live, and Sam, this cold isn't letting go yet. Reporter: You're exactly right, whit. We've got another full day of this early brutal chill. Take a look at tomorrow morning's step pra Sures, because this arctic express jumped on the jet stream. The early morning chill for Friday, look at this, 35 in Chicago, but thousand look down to the south. Nashville all the way into Raleigh, we're looking at the 20s and the 30s. It's at least ten degrees cooler than Normal in those southern areas. Here's the good news, whit. When we get into the weekend, we get a mild push of air, and the major cities on the east coast will jump, in some cases, 20 degrees, back to above Normal temperatures. Now, whit, this was a big deal. When central park records the second-coldest Thanksgiving ever, we've had -- it's one of the earliest record-keeping places we have in the country. Since the 1800s. So, this is a really big, early chill, whit. And we got a little while longer to hang in there. Sam champion, thank you. And on this Thanksgiving
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