ferocious storm system with very bad timing is creating all kinds of trouble. Look at the countdown clock, one of the busiest travel days of the year hours away and this is the storm, power up and on... See More
ferocious storm system with very bad timing is creating all kinds of trouble. Look at the countdown clock, one of the busiest travel days of the year hours away and this is the storm, power up and on the move, arctic air, downpour, strong winds and tornados. The national service issues watches, warnings and advisories in 20 states tonight and so many wondering will they make it home for thanksgiving. Abc's weather editor sam champion starts us off. Good evening, sam. Reporter: Good evening, george. There is a light, cold rain in central park. This prethanksgiving storm has made it on the east coast. Look at the radar. It's the entire east coast, every eastern state from the gulf coast to maine is getting something outs of this storm. There is still the possibility of severe weather in north florida all the way to coastal a carolinas. Let's head south a little bit though because that's the area that took the brunt of the storm during the day today deep into atlanta where they had a break in the rain for a couple of hours but now back into rain and there is even a possibility of that cold air bringing light snow in the morning. Our gio benitez is standing by in atlanta right now. Good evening. Reporter: Good evening to you from a wet atlanta, so much rain here all day long, so many accidents and the timing couldn't be worse. For millions of americans tonight, getting to grandma's house for thanksgiving means doing battle with mother nature. It's going to be a hectic day on tap for us. Heading home for the holidays could be more difficult. Monitoring the ugly weather conditions across metro atlanta. It will be a white thanksgiving. Reporter: In portland maine high winds are causing havoc, in virginia the morning freeze turned into afternoon downpoors. Some sleet and some freezing rain, and this morning, my drivewayas solid ice. Reporter: Up and down the east coast, this storm is causing a traffic nightmare. Hundreds of accidents just as tens of millions are expected to drive for thanksgiving. In birmingham, alabama, this morning, an 18-wheeler sliding off the road and ending up on its side. And in pittsburgh, a car slid off the road and was left dangling over a hillside. In north carolina, mostly rain. A driver ending up in a ditch. I hydroplaned over here and came off and slid around. Here in atlanta, we rode along with the department of transportation's heroes unit -- the first responders for traffic accidents. The number one danger? Black ice. A lot of times in weather like this you don't see that ice on the road? No, they won't know until they're hydroplaning. Reporter: To keep safe on the roads, a great tip from aaa they tell us -- don't use cruise control. In slippery conditions, you need to be able to ease off the gas quickly, and you can't when your cruise control is on. So that's the mess on the ground but if you are flying up, the air is messy, too. For that part of the story we turn to abc's david kerley at o'hare international airport in chicago. David, good evening. Reporter: Good evening. This is united's o'hare airport command center, the busiest time of the year. Over all tonight there are 7200 flights in the air. In atlanta one in three flights was delayed today. There is another map they're interested in in chicago. It's that map sam showed you, the weather map and the storm which could cause huge airline delays. Worried about the weather passengers are hitting airports early, but in some cases even that is not enough. I actually had a job interview in little rock and i got stuck in houston last night because my flight from little rock was delayed. Reporter: That's just the start. Tomorrow 2.4 million people will fly, the second busiest day of the year, that is if they can fly. The east coast storm could cancel or delay flights. For airlines, the pressure is on. Does it get any bigger than thanksgiving? I would say the combination of thanksgiving and christmas is indeed our super bowl, our chance to shine. Good job. Reporter: We joint this united crew as they turned around this 737 in less than an hour and a half, cleaning, refuelings, unloading and reloading. I even joined them in the belly of the plane. Man, is that heavy. Reporter: This jet headed to l.A. Left on time. Will others be as lucky tomorrow? As this storm sits over the east coast, major hubs could be effected, maybe the biggest one new york. One in ten flights goes through new york, boston and philly at risk as well. By the way that l.A. Flight landed 32 minutes early that we helped locate. Let's bring sam back. Walk us through this forecast for the next 24 hours. Reporter: I think we're done with early flights coming out of the east coast for little while and we'll show you why. Look at the path over the next 24, 36 hours. Even keeping some snow in the mix here. By thursday, by thanksgiving day, this storm is out of the u.S. And it's taking most of the snow and rain with it. Here's the snow we're talking about, from knoxville to buffalo to burlington. Some of these areas for buffalo, erie, cleveland, this is an all snow event. The weste part of new york, I'm convinced you may see 18 inches of snow. Look at the rain here, generally two to four along the i-95 corridor. Rain won't cause delays for airports but we're expecting strong winds, 30, 40, 50 miles per hour wind gusts which will delay flights. What does that mean for the macy's parade? Reporter: All right, this is not necessarily good news. They'll make that decision thursday morning when they get a chance to look at the real winds, but the forecast for that time period is a 20, 25 mile per hour wind gusts up to 40 miles per hour. The threshold for pulling those balloons is 23 mile per hour steady wind with gusts up to 30 so it's going to be very, very close. That is close. You, sam and the weather team tracking the travel mess throughout the night. We move to washington and a
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