Nearly 50 million Americans from the Midwest to the Northeast are on alert as a developing winter storm is expected to bring an impactful ice threat that could knock out power and lead to treacherous travel conditions across the region.

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Nearly 50 million Americans from the Midwest to the Northeast are on alert as a developing winter storm is expected to bring an impactful ice threat that could knock out power and lead to treacherous travel conditions across the region.

Computer forecast models are coming into agreement that the storm, which is connected to a series of powerful atmospheric river storms slamming the West Coast , will develop across the Plains on Wednesday before gaining strength as it sweeps east across the U.S.

As the system moves off to the east, a strong southerly jet stream will kick in, pulling in warm, moisture-rich air across the eastern half of the nation. That setup will then lead to the development of a warm front , separating subfreezing air to the north from record-breaking warmth to the south.

The issue is that the warm air will move in above a shallow layer of subfreezing air near the ground.

The FOX Forecast Center said that will lead to a large swath of impactful freezing rain that will fall from Iowa to New England .

The warmer air aloft will be so potent that the FOX Forecast Center said you’d have to travel to northern Minnesota , Wisconsin and Michigan to find snow with the system.

Freezing rain is expected to break out on Wednesday afternoon in the mid- Mississippi Valley and then swoop into the Great Lakes region by Wednesday night.

Winter weather alerts are already in place from northwestern Missouri through southern New England.

The National Weather Service office in St. Louis has urged people to prepare for impacts.

"Slow down and use caution while traveling," forecasters said . "Prepare for possible power outages."

The Thursday morning commute is expected to be extremely dangerous on untreated roads in cities like Chicago ; Fort Wayne , Indiana ; and Columbus and Cleveland in Ohio .

Areas to the east are expected to see a greater potential for significant icing, especially in western Maryland and the Laurel Highlands of Pennsylvania .

Winter Storm Watches have been posted in the region, including cities like Clarion , Altoona and Bedford in Pennsylvania.

Power outages and tree damage are most likely in those areas due to ice accretion greater than a quarter-inch.

Some utility companies in the region spent the first days of the workweek preparing for what could be a widespread impact event.

Outside of that region, freezing rain is expected to fall along the busy Interstate 95 corridor from Washington to southern New England.

The FOX Forecast Center said that from the New York City area northward, the cold air will be deep enough that snow will be a concern during the onset of the winter weather .

Cities like New York City; Hartford , Connecticut ; and Boston could see snow fall during the middle of the Thursday morning commute.

That could wreak havoc on the roads, but the FOX Forecast Center said that much like in the Midwest, warm air will move in, changing the snow to either freezing rain or plain rain.

Any snow left behind will nearly completely melt.

But farther to the north across northern New England, the snow will continue through the day on Thursday and may not change over north of Interstate 90. The FOX Forecast Center said that locations picking up 6 inches of snow or more would likely be found there.

The system will then quickly exit New England by Thursday evening, leaving mainly dry conditions in its wake on Thursday night and Friday.

However, another winter storm could impact many of these same areas over the weekend.