Average Date of First Snow in Illinois

I have noticed that the average date of the first snow is a popular search term on the blog, so here is the reposting of the median dates of the first measurable snowfall of the season in Illinois. This map is based on 1971-2000 data. While it is not based on the current 1981-2010 averages, the map is still relevant for the purpose of getting an idea of the dates. Measurable snowfall means at least a tenth of an inch.

Median Date:

In the northern third of Illinois, the first snowfall occurred around Thanksgiving. The dates switch from November to December once you reach central Illinois (just north of a line between Quincy and Champaign). By the time you reach Carbondale, the date can be as late as December 20. From this you can see that we are by no means behind schedule this year.

date of first snow

Early Date:

In about 10 percent of the cases, the first measurable snow occurred as early as November 5 in northern Illinois to November 20 in far southern Illinois.

Late Date:

In about 10 percent of the cases, the first measurable snow occurred as late as December 20 in northern Illinois. South of a line from Quincy to Champaign (Interstate 72), it can occur after the New Year. From Carbondale southward, Illinois, it can be January 20th before the first snow arrives.

Current Status

By the way, here is where the snow has fallen in the Midwest so far – nothing close to Illinois yet.


2 Replies to “Average Date of First Snow in Illinois”

  1. Hi Jim, With the forecast being warmer and drier in Southern Illinois this winter, when would you roughly guess we will have snow and ice for the first time this winter?

  2. Hi Sal, sorry for not responding to your question sooner. No snow yet for southern IL and nothing in the forecast any time soon. It would not surprise me if it is January before you see anything.

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