Chicago Snowfall Totals & Accumulation Averages
This page pulls together information on when, how much and how often Chicago, Illinois has snow.
There are data and descriptions here of how many days it snows and the total amount of snowfall that Chicago usually gets. There are also monthly and yearly counts of the days that the city normally has heavy snowstorms and deep snow accumulated on the ground. Plus there's information on when Chicago can expect the first and last snowfalls of the season.
The first set of monthly snow totals are averages for 2010 to 2019. All the other numbers are averages, based on climate data gathered from 1991 to 2020 at the Chicago O'Hare International Airport.
How Often it Snows in Chicago
The next two tables list monthly and yearly totals for amount of snow and how many days it snows at least 0.1 inches (0.25 centimetres) at O'Hare.
These averages don't show how much Chicago's snowfall varies from year to year.
In December, for instance, one in four years totals over 10.3 inches of snow. Another 25 percent of years receive less than 1.6 inches for the month.
Similarly in January, fresh snowfall in the heaviest years amounts to 14.6 inches or more, while the lightest years get 5.5 inches or less.
Snow in February ranges from over 20 inches in heavy snowfall years to under 2.6 inches in light years.
When Chicago Has Its First & Last Snowfalls
Over the long-term Chicago has averaged a dusting of 0.2 inches of snow during October. But in most years October has no snow. Typically, just one in five years see snow that early.
Chicago's first snowfall of winter usually arrives in November. Less commonly, snow doesn't arrive here until December.
While the season's last snowfall most often happens in April, the month can also be free of snow.
Chicago is normally free of snow every year from May to September.
How Many Snowstorms Chicago Has
Chicago gets snow more often than many places in Illinois. But most days with snowfall in Chicago result in just a skiff of less than an inch left on the ground. Normally on 11 days a year at least an inch of snow lands in one day.
Snowstorms of over five inches a day occur just once or twice a year on average. Major blizzards that dump ten inches or more in one day are rare events, happening about once a decade.
How Much Snow Normally Accumulates in Chicago
For less than half of winter days, Chicago has at least an inch of snow on the ground.
Typically on 15 days in a winter, the snow covering Chicago gets to five or more inches deep. On three of four of those, the snow builds up to over ten inches.
Jay Lawrimore, Ron Ray, Scott Applequist, Bryant Korzeniewski, Matthew Menne. 2016. Global Summary of the Month and Year, Version 1.0. NOAA National Centers for Environmental Information.
NOAA National Centers for Environmental Information (NCEI). Climate Normals.