A drone view shows the aftermath of a snowfall in this screen grab obtained from social media video, in Crystal Lake, Illinois, U.S., November 30, 2025. Instagram@radiojoecicero/via REUTERS

By Rich McKay

Dec 2 (Reuters) - An intensifying weather system was expected to bring heavy snow or rain to parts of the U.S. Midwest, the Appalachians and the Northeast on Tuesday, with more than 50 million Americans under a winter storm advisory.

Up to a foot of snow is forecast across the Ohio Valley, Pennsylvania, upstate New York and into New England, with some areas getting up to an inch an hour, said Ashton Robinson Cook, a forecaster at the National Weather Service's Weather Prediction Center.

"If you don't have to be on the roads today, stay home," Cook said. "In areas of heavy snow, it's best not to travel. But if you have to go out, give yourself a lot of extra time."

Between three and five inches of snow had fallen by early Tuesday afternoon across Indiana, Pennsylvania, Central New York and parts of New England, forecasters said, with snow expected to keep falling throughout the day.

Hundreds of school districts from Cincinnati and western Pennsylvania to New Hampshire and Maine announced school closures or delayed openings.

The snow is expected to miss some areas east of Interstate 95, a major north-south route that hugs the Atlantic Coast, but residents can expect rain and freezing rain up and down the corridor, including in Washington, Philadelphia and New York City, where temperatures will hover above the freezing point.

Further north in Boston, the precipitation may toggle between snow and rain later on Tuesday, Cook said.

In addition, some areas along the central and southern Appalachians will see freezing rain and slick roads.

Chad Merrill, a senior meteorologist with AccuWeather, a private weather forecasting company, said that more winter weather was on the way later this week.

"We'll see an Arctic cold front coming down through Canada on Thursday that could bring some more snow showers in the Northeast and Mid-Atlantic," he said. Accumulations of an inch or so are expected by Friday.

The bad weather will also dip farther south, bringing snow, sleet and freezing rain to the Appalachians, including the western parts of the Carolinas, he said.

(Reporting by Rich McKay in Atlanta; Editing by Frank McGurty, Chizu Nomiyama and Aurora Ellis)