Here's why the blizzard forecast just got so much worse

Less than two days ago, the weather forecast from Philadelphia to Maine featured a chance of a few snow flurries from Monday into Wednesday. There was no mention of a historic blizzard. Not even a snowstorm. Yet on Sunday afternoon, there was New York City Mayor Bill de Blasio warning residents of "one of the largest snowstorms in the history of this city," and officials up and down the coast echoing the same message in other cities

So, what changed, and why is the forecast so dire? And are officials who are warning of a historic storm overdoing it?

See also: NYC Mayor de Blasio: Expect 'one of the largest snowstorms in the history of this city' Read more...

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