Where Do Winter Storms Come From?

Source: AccuWeather

In North America, Winter Storms often happen when a cold and dry air mass or Cold Front, moves down from Canada and collides with a warmer and humid air mass or Warm Front, from the Gulf of Mexico.

Source: WeatherSTEM

In the Southern United States the boundary between the two air masses produces precipitation that falls as rain. As you progress Northward, precipitation falls as snow in colder regions.