By one calculation, the single worst day for can collations this winter. Travelers delayed a kind of domino effect. ABC's David Kerley shows us. Reporter: Massive snow plows raced to clear and open... See More
By one calculation, the single worst day for can collations this winter. Travelers delayed a kind of domino effect. ABC's David Kerley shows us. Reporter: Massive snow plows raced to clear and open runways as hundreds of thousands of passengers -- I've had three flights cancelled. Reporter: -- Remain grounded. We were on a flight at 9:00 A.M. That was rebooked to 11:10 and is now rebooked to 7:00 tonight. Reporter: While Washington's runways were closed, a few flights got in and out of northeast airports, but pilots were warned of slick runways. Airlines wasted no time cancelling flights, letting many aircraft sit out the storm. That stat, one in six flights cancelled, translates to 6,400 flights, which rippled throughout the country's entire airspace. Airlines even moved planes out of the east and will start moving them back tonight. Atlanta was trying to bounce back from its storm, long lines there today. And tonight, a unique look at what workers do all season, spraying de-icer, to prep a plane for takeoff. You kind of can tell the different colors of the ice. If there's ice and snow are present, your job is to get it off. Reporter: This is a gallon of anti-freeze. In Philadelphia alone, they'll use 20,000 gallons of this. Tomorrow should be a much better day. All right, David, 20,000 gallons in one city alone and what a month this has been by our count right here in new York, seven storms in seven weeks. Tonight a lot of people across this country are praying are for warmer weather, ABC meteorologist ginger zee is standing by with details. Reporter: We're switching back to snow. The back end of this nor'easter is going to flow in. Let me tell you what's going to happen, you're getting more snow tonight anywhere from parts of Maryland, Delaware already getting it, up through New York City. Friday, Valentine's day, it's clear. Look at Cincinnati, a new snowstorm will slide across on Friday night through early Saturday morning, it looks like we could pick up more snow as we go through the weekend and look at this, Diane, if it feels like it has been nonstop, you're right. In New York City, seven days an inch of snow or larger, 40 inches just since the beginning of 2014. Philadelphia, now in their fifth snowiest year ever, last year, just a half a foot, average, more like 12 and then you got 14 there. 53.5 is where we're at this year. Diane? Thank you, ginger zee. You our team will be covering
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