Weather in Chicago in August
August in Chicago is mild with average temperatures around 22.6°C (72.7°F). Expect significant rainfall with 105mm across approximately 13 days.
Data Note: Temperature values are 2001–2020 satellite/reanalysis grid averages from NASA POWER and may differ from airport station normals by a few degrees.
Temperature
High
25.1°C
77.2°F
Low
20.0°C
68.0°F
Precipitation
105 mm
4.1 inches
~13 rainy days
Conditions
Humidity
77%
Comparison to Adjacent Months
August is 3.4°C warmer than September.