When Does the First Snow Fall in Missouri & Illinois on Average?
When does the first snow fall for Missouri and Illinois on average? Based on past years, it's likely sooner than you think.
This is a question I researched just out of curiosity. I realize that every year is different, but if you were to average out all of the recorded years by the National Weather Service what day could you point to as the most likely day for the first measurable snowfall of the season. The answer is...complicated.
A few years ago, The Weather Channel asked the same question and came up with some dates. In general, it shows that the first snow in northeast Missouri and west-central Illinois generally falls sometime in November. Their map shows us right on the edge between sometime in November and December. That's not good enough for my curiosity.
The average first day for snow according to their data is December 3 for St. Louis. For Chicago, that average first day of snow is much sooner at November 16.
I decided to not just trust one source and found an article by KMIZ in Columbia that said their National Weather Service data said the average first day for snow in mid-Missouri was November 29.
What about recent years? Fox 2 out of St. Louis said that the first snowfall for 2017 was December 23. In 2018 and 2019, it was around November 11-12. For 2021, there really wasn't any real snowfall for St. Louis until later in January. Go figure.
Based on the multiple sites, the best plan is to be on the lookout for snowfall possibilities starting in mid-November and expect something by mid-December at least. Sure, there are anomalies that could cause a snow event sooner or later than these averages, but this is a good starting place to start preparing our shovels for use.