WISCONSIN — While September is widely associated with the last days of summer and the beginning of fall, Wisconsin’s weather history shows that the possibility of snowfall during this month is not entirely out of the question.
According to records from the National Weather Service and the Midwestern Regional Climate Center, measurable snow has, in fact, fallen in Wisconsin during September, though such occurrences are rare.
The earliest widespread measurable snow in the state’s history happened on September 20, 1945, when parts of northern Wisconsin reported accumulations of around one inch.
Another notable event occurred on September 26, 1942, when portions of northern and central Wisconsin received light snow.
Northern regions of the state, particularly areas bordering Lake Superior such as Ashland, Iron, and Vilas Counties, are most likely to see snow in September due to their proximity to colder air masses moving in from Canada.
In contrast, southern Wisconsin—including cities such as Madison and Milwaukee—has virtually no record of measurable September snow. At most, these areas might experience flurries or sleet during an unusually cold spell.
Climatologists note that Wisconsin’s average first measurable snowfall typically occurs in late October or early November, depending on the region.
For example, Madison usually sees its first snow by early November, while far northern locations like Hurley or Ironwood, just across the state line in Michigan’s Upper Peninsula, often record snow in October.
The rarity of September snow in Wisconsin means that most residents will never see it in their lifetimes. However, the state’s climate records make it clear that, while highly uncommon, it has happened before and could happen again under the right atmospheric conditions.
In short, Wisconsin’s September weather is far more likely to feature warm afternoons and cool evenings than snowflakes, but history shows that a sudden hint of winter remains within the realm of possibility.
