INDIANA — Snowfall in Indiana during the month of September is an extremely rare event, but historical weather records show it is not impossible.
According to data from the National Weather Service (NWS) and the Midwestern Regional Climate Center, Indiana’s climate typically sees its first measurable snow in late October or November, depending on the location within the state.
Southern Indiana averages its first measurable snowfall in late November, while northern areas, particularly near Lake Michigan, often see their first snow in late October.
However, snow has been documented in Indiana during September, though only on rare occasions and generally in the northern part of the state.
The earliest measurable snowfall ever recorded in Indiana occurred on September 25, 1942, when South Bend received 0.9 inches of snow. Trace amounts have also been reported in other northern locations in late September during unusually cold weather patterns.
These occurrences are statistical outliers. Climate records show that the probability of measurable snow in Indiana in September is less than one percent. Most years pass without any sign of snow until well into autumn.
While unusual, the few documented instances of September snow illustrate Indiana’s potential for highly variable weather, influenced by its location in the Midwest and exposure to early-season cold air masses from Canada.
