A huge winter storm is expected to affect millions across 22 states

Residents in 22 states are under winter weather alerts this week with a huge storm expected to bring heavy snow and high winds, the National Weather Service says.

The storm is expected to "deliver a large swath of heavy snow from the West Coast to the Northeast through Thursday," the NWS said on Tuesday.

The winter storm will begin in California with heavy snow accumulating in high-elevation areas such as the Sierra Nevada mountains — though there's a chance residents in central California valleys will also receive a light dusting of snow on Tuesday.

The deepening low pressure system will carry widespread, gusty winds as high as 80 mph across the West and the High Plains states on Tuesday and Wednesday.

The axis of heavy snow is expected to expand to Wyoming, Montana, South Dakota, Iowa and Minnesota.

"As impressive as the snowfall event will be across the West, potentially even more impressive and impactful will be the blizzard that is expected to develop from the High Plains through the Upper Midwest, especially Wednesday and Thursday," the NWS Weather Prediction Center wrote.

Near Minneapolis, the NWS reported on Tuesday that historic snowfall is possible. The local NWS office added that the storm "could very well break top five snowfalls in the Twin Cities dating back to 1884."

There's also a chance of heavy rain and flash flooding in parts of Missouri, Illinois, Indiana and Michigan, the NWS says.

Simultaneously, however, across the Southeast and parts of the Midwest, 150 million Americans will experience highs of over 70 degrees.

"These highly anomalous temperatures are forecast to continue later into the week," the NWS said on Tuesday, referencing the mesh of unusual cold and warmth that people will experience.