Weather in Chicago in September
As an Amazon Associate we earn from qualifying purchases. We also earn commission from other retail partners. Links below are affiliate links.
Book now, pay at pickup — compare Hertz, Avis, Budget, Sixt and 800+ rental companies for September in Chicago.
Compare car hire prices → Affiliate link — we earn a commission at no extra cost to youChicago in September is warm — daytime temperatures average 23.5°C, dropping to 15.7°C at night. The month is fairly wet (8 rainy days on average), with roughly 9.5 hours of sunshine a day. This is peak season for good reason — conditions are close to ideal. For the complete picture, see the best time to visit Chicago — every month compared. Once you know when to go, find your Chicago packing list at 247PackingList.
Get ready for Chicago in September
Search flights to Chicago
Compare 100+ airlines for September — one search, best price.
Search Flights →Thermal travel layers
Pack proper layers — winters are genuinely cold and evenings drop fast year-round.
Check Price →What to pack for Chicago in September
- Light layers
- Sunscreen
- T-shirts and light trousers or shorts
- Compact travel umbrella
- Waterproof jacket
- Quick-dry clothing
Compare all months in Chicago
| Month | High | Rain | Rating |
|---|---|---|---|
| January | 1.0°C | 66.1mm | 8/10 |
| February | 1.2°C | 64.3mm | 8/10 |
| March | 8.5°C | 89.6mm | 10/10 |
| April | 13.3°C | 92.4mm | 10/10 |
| May | 18.9°C | 108.9mm | 9/10 |
| June | 25.9°C | 103.8mm | 9/10 |
| July | 27.2°C | 172.8mm | 9/10 |
| August | 27.0°C | 111.8mm | 9/10 |
| September | 23.5°C | 106.1mm | 9/10 |
| October | 16.4°C | 130.3mm | 9/10 |
| November | 9.9°C | 37.4mm | 10/10 |
| December | 4.8°C | 65.3mm | 8/10 |
Full month-by-month guide: best time to visit Chicago →
For facts about United States — currency, language and dialling code — see our United States country guide at 247CountryInfo. Travellers also find it useful to keep a Chicago travel guide to hand. Check clothing sizes in United States before you shop.
Frequently Asked Questions
Is September a good time to visit Chicago?
September rates 9/10 for visiting Chicago — excellent time to visit. Expect average highs of 23.5°C, 106.1mm of rain across the month and about 9.5 hours of daily sunshine.
What is the temperature in Chicago in September?
In September, Chicago has average highs of 23.5°C (74.3°F) and average lows of 15.7°C (60.3°F).
Does it rain in Chicago in September?
Some rain is likely. Chicago averages 106.1mm across about 8 rainy days in September, so a light waterproof layer is worth packing.
What should I wear in Chicago in September?
For Chicago in September (23.5°C highs / 15.7°C lows), pack light layers plus sunscreen, t-shirts and light trousers or shorts, compact travel umbrella.
More essentials for Chicago in September
Packing cubes
Keep the bag organised whatever the weather — compression cubes for every size.
Check Price →Travel first aid kit
Compact TSA-friendly kit for peace of mind wherever you travel.
Check Price →Last updated:
Climate data sourced from Open-Meteo (open source, open data licence). Monthly averages calculated from 2020–2023 historical data. Weather can be unpredictable — always check a live forecast before travelling.