Snow, freezing rain and sleetthreaten to snarl travel for those heading home after the Christmas holiday across parts of the Great Lakes, Northeast and Mid-Atlantic, forecasters said.
Snow is expected to develop on Christmas Day in the Northeast and later in the day in the upper Midwest. By Dec. 26, a second system will bring a wintry mix to a stretch from Michigan across Pennsylvania and into the upper Mid-Atlantic, the National Weather Service said.
"This winter storm is likely to generate treacherous travel conditions and delays following Christmas Day," the weather service said.
An estimated 122.4 million Americans are expected to travel at least 50 miles over the end-of-year holiday season, including nearly 110 million who will travel by car, according to AAA.
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Snow storm could snarl travel, cause power outages
The fast-moving storm could impact millions with travel disruptions and power outages, AccuWeather reported. Several inches could accumulate on roads. A buildup of ice and snow can also cause downed tree limbs and power lines.
A quarter of an inch of freezing rain accumulation is expected across Pennsylvania, while snow is set to form in the upper peninsula of Michigan and "moderate to heavy snow" will reach New England on Dec. 26 and into Dec. 27, the weather service said.
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More than 6 inches of snow could fall in parts of New York, northeast Pennsylvania and northern New Jersey. The Washington, Baltimore and Philadelphia metro areas could also see hazardous ice.
"This could be the biggest snowstorm of the season so far for New York City," said AccuWeather Senior Meteorologist Tyler Roys.
How much snow is expected in this winter storm?
The greatest snowfall will happen in interior areas from the Catskill Mountains to northeastern Pennsylvania, with 6 to 12 inches, according to AccuWeather. The outlet predicted this much snow in major cities:
Hartford, Connecticut: 3-6 inches
New York City: 3-6 inches
Syracuse, New York: 3-6 inches
Boston: 1-3 inches
Philadelphia: 1-3 inches
Baltimore: Coating to an inch
Washington: Coating to an inch
This article originally appeared on USA TODAY:Winter storm to bring snow, icy conditions for post-Christmas travel