Green Bay, Wisconsin, is situated in a region defined by its northern latitude and its proximity to the Great Lakes, factors that significantly shape its winter climate. The city experiences a humid continental climate, which features distinct seasons with cold, snowy winters. Understanding how much snow the area receives involves examining long-term averages, monthly patterns, historical extremes, and the specific geographical influences at play.
Typical Seasonal Accumulation
The official, long-term average annual snowfall for Green Bay is 55.6 inches, based on the 1991 to 2020 climate normals recorded at Austin Straubel International Airport. This figure represents the total accumulation from the first measurable snow of the season to the last. The city’s snowy period typically spans just over five months, beginning in early November and concluding in mid-April.
The annual total is delivered over approximately 40 days each winter that see at least 0.1 inches of new snow accumulation. This consistent, moderate snowfall is a result of the city’s location within the path of many major midwestern winter weather systems. The period from November to April is characterized by temperatures that remain cold enough for precipitation to consistently fall as snow.
Monthly Distribution of Snowfall
The seasonal snowfall is not evenly distributed across the winter months, instead concentrating into the heart of the cold season. On average, the peak of the snowfall season occurs in January, which sees the greatest accumulation at 14.3 inches. December follows closely as the second snowiest month, averaging 13.1 inches of snowfall. These two months alone account for nearly half of the city’s annual total.
February contributes another significant portion of the seasonal total, recording an average of 12.0 inches. The start and end of the season are comparatively lighter, with November averaging around 3.1 inches and March seeing an average of 8.1 inches. By April, the monthly average drops to 4.7 inches as temperatures rise and the season draws to a close.
Record Snowfall Events
While the averages define a typical winter, historical extremes showcase the potential for heavier snowfall. The snowiest winter season on record for Green Bay was the 1887–1888 season, which accumulated 147.7 inches of snow. This total is more than two and a half times the current seasonal average, illustrating the high variability in annual snowfall totals.
The largest single snowstorm event on record occurred during that same historic winter. A storm on March 1–2, 1888, dropped a total of 29.0 inches of snow over the two-day period. The single calendar-day record for Green Bay was set during the initial day of this storm, with 24.0 inches falling on March 1, 1888.
Local Factors Driving Snow Totals
Green Bay’s geographical position dictates much of its winter weather. The city’s location in the upper Midwest ensures it is frequently subjected to cold air masses that originate in Canada. These cold, dry air intrusions provide the necessary sub-freezing temperatures for snowfall to occur.
The city’s relationship with Lake Michigan also influences its snow totals, though less intensely than the eastern shore of the state. Green Bay sits on the western side of the lake, which means it is generally upwind of the lake-effect snow phenomenon when cold air blows from the prevailing northwest. Lake-effect snow only occurs when winds shift to an easterly or northeasterly direction, which allows the air to pick up moisture from the lake before dropping snow on the western shore. The majority of the city’s accumulation comes from larger, organized low-pressure systems that move across the region, rather than localized lake-effect events.