ILLINOIS — A snowfall of up to a foot from a single weather system in March is uncommon in Illinois, but historical weather data shows that it is still possible under the right conditions.
March is considered a transitional month across Illinois as winter gradually gives way to spring, according to the National Weather Service.
Average temperatures typically begin to rise, but cold air can still move into the region from Canada. When that cold air coincides with a strong storm system tracking through the Midwest, the atmosphere can still support heavy snowfall.
Past weather records show several examples of significant March snowstorms in Illinois. One of the most notable occurred during the 1993 Storm of the Century, which brought widespread snowfall and blizzard conditions across parts of the Midwest, including Illinois. Some locations in the state reported snowfall totals approaching or exceeding a foot during that event.
Another major late season storm occurred in March 2015, when a strong low pressure system moved across the central United States and produced heavy snow across portions of northern Illinois and the Chicago area. In several locations, snowfall totals reached around 9 to 12 inches.
Meteorologists note that March snowstorms in Illinois often occur when a strong low pressure system develops in the Plains and tracks toward the Great Lakes. These systems can pull in moisture from the Gulf of Mexico while cold air remains in place across the Midwest, creating favorable conditions for significant snowfall.
While large snowfalls become less common as spring approaches, historical climate data shows that Illinois can still experience substantial winter storms in March. Under the right atmospheric setup, a single storm system can produce snowfall totals approaching or exceeding a foot in parts of the state.
