Since the winter of 1880-1881, the Twin Cities climate records show a measurable amount of snowfall for the month of October approximately 33 percent of the time….one year in every three. So inevitably this leads to the question “is it a predictor of a snowy fall or exceptionally snowy winter season?”
The answer is emphatically NO! Examining the snowfall records for the Twin Cities, when measurable snowfall occurs in the month of October it is associated with an exceptionally snowy fall season only about 20 percent of the time. Similarly it is associated with an exceptionally snowy entire winter only about 25 percent of the time. This is not a strong statistical correlation.
These general historical statistics make it hard to use snowfall in October as a predictor of snowfall later in the season or throughout the winter. However, imbedded in these historical statistics are some striking examples of extremely challenging winters in Minnesota that began with significant October snowfalls. Those are the winters of 1880-1881, 1916-1917, and 1991-1992. Each of these winter seasons arguably began early with snowfalls of several inches in October. The following months brought even heavier snows and many blizzards to the Twin Cities area. The seasonal total in 1991-1992 was 84.1 inches, while that of 1916-1917 was 84.9 inches. And for 1880-1881, the famous Laura Ingalls-Wilder “long winter” on the Minnesota prairie, the Signal Corps Office in downtown Saint Paul reported an incredible 110 inches of snowfall.
You can read more about these winters in my “Minnesota Weather Almanac” still available in most bookstores.