Is Chicago hot in September?
Days are typically warm at 24.8°C, while nights average 15.1°C.
United States · 1991–2020 normal
Chicago in
September.
Typical September weather in Chicago: 24.8°C by day, 15.1°C at night, 68 mm of rain over 6.7 wet days. These are measured 1991–2020 station normals, not a forecast.
Typical high24.8°C
Typical low15.1°C
Rain68 mm
Wet days6.7
In the year-round weather comparison, September scores 89 out of 100, the highest of the year. Daylight is calculated as 12 h 26 from latitude 41.85°. Open-water sea temperature is 20.1°C (4 km from the place centre).
September at a glance
What is Chicago like in September?
Plain answers from the measured climate record—not a forecast or a promise about a particular trip.
Does it rain much?
The measured monthly average is 68 mm across about 7 wet days.
How much daylight is there?
There are about 12 h 26 between sunrise and sunset at mid-month, calculated from the place latitude.
Is September a good time to visit?
September is the strongest month in our year-round weather comparison.
The evidence behind this page
One month,
from the same station.
- Place identity
- GeoNames 4887398
- NOAA station
- USW00014819 · CHICAGO MIDWAY AP
- Station distance
- 11.4 km from the place centre
- Coverage
- Good coverage · 23 usable years
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.
Next step
Choose your month.
Then plan the details.
The weather comparison for Chicago is based on climate evidence, not payments from travel companies. Flight, accommodation and activity links will be clearly labelled when they are added; there are no booking offers on this page today.
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