Cook County · Illinois
Chicago, IL weather averages
NOAA climate normals for 1991-2020, measured at Chicago Univ, 11.5 km from the city centre — month by month temperature, rain and snow.
Quick answer
Chicago averages a daily high of 60.7°F and a daily low of 44.7°F across the year, with 37.96 inches of precipitation. July is the warmest month at 84.6°F and January the coldest at 20.9°F.
- Average annual high
- 60.7°FWarmest month July
- Average annual low
- 44.7°FColdest month January
- Precipitation per year
- 37.96 inWettest month May
- Snowfall per year
- —93.3 days at or below 32°F
Chicago weather month by month
Normal daily high and low, precipitation and snowfall for each month, 1991-2020.
| Month | High °F | Low °F | Precip in | Snow in | Range |
|---|---|---|---|---|---|
| January | 33.8 | 20.9 | 2.25 | — | 20.9 to 33.8 degrees |
| February | 38 | 24.4 | 2.04 | — | 24.4 to 38 degrees |
| March | 47.7 | 32.6 | 2.79 | — | 32.6 to 47.7 degrees |
| April | 59.6 | 41.8 | 3.35 | — | 41.8 to 59.6 degrees |
| May | 70.3 | 51.7 | 4.07 | — | 51.7 to 70.3 degrees |
| June | 80.4 | 61.3 | 4.05 | — | 61.3 to 80.4 degrees |
| July | 84.6 | 67.4 | 3.78 | — | 67.4 to 84.6 degrees |
| August | 83.2 | 66.6 | 3.81 | — | 66.6 to 83.2 degrees |
| September | 76.6 | 59 | 3.13 | — | 59 to 76.6 degrees |
| October | 64.8 | 47.5 | 2.88 | — | 47.5 to 64.8 degrees |
| November | 50.8 | 37.7 | 3.23 | — | 37.7 to 50.8 degrees |
| December | 37.3 | 24.9 | 2.58 | — | 24.9 to 37.3 degrees |
Source: NOAA NCEI, U.S. Climate Normals 1991-2020 — station USW00014892, Chicago Univ · rates as published for 1991-2020 normals
How to read Chicago climate normals
What a climate normal is, and what it is not.
A normal is the average of thirty years of daily observations at one station — here Chicago Univ, 11.5 km from the centre of Chicago. It describes a typical year, so any single year will run warmer, cooler, wetter or drier. Readings taken at an airport on the edge of town usually sit a degree or two below a dense downtown on summer nights. Chicago sees about 18.2 days a year at or above 90°F and about 73.9 days with a tenth of an inch of precipitation or more.
Keep going
Other Chicago data on this site.