No
you don't need a jacket based on the weather in Illinois, USA 1 second ago
85°F29°C & Mostly Clear
Wind is 6 mph9 km/h from the Northeast, gusting to 8 mph13 km/h
| September 16 | ||||
| 7pm | 83°F28°C | 6 mph10 km/h Northeast | Clear | |
| 8pm | 78°F26°C | 5 mph9 km/h Northeast | Clear | |
| 9pm | 74°F24°C | 6 mph10 km/h East | Clear | |
| 10pm | 72°F22°C | 7 mph11 km/h East | Clear | |
| 11pm | 70°F21°C | 7 mph12 km/h East | Clear | |
| September 17 | ||||
| 12am | 68°F20°C | 6 mph10 km/h East | Clear | |
| 1am | 66°F19°C | 6 mph9 km/h East | Clear | |
| 2am | 64°F18°C | 5 mph8 km/h East | Mostly Clear | |
| 3am | 62°F17°C | 4 mph7 km/h East | Clear | |
| 4am | 61°F16°C | 4 mph7 km/h East | Clear | |
| 5am | 60°F15°C | 4 mph7 km/h East | Mostly Clear | |
| 6am | 59°F15°C | 4 mph7 km/h East | Partly Cloudy | |
| Date | Low | High | Wind | Day | Night |
|---|---|---|---|---|---|
| September 16 | 60°F15°C | 87°F31°C | 3 mph5 km/h from Northeast | Clear | Mostly Clear |
| September 17 | 58°F14°C | 86°F30°C | 4 mph7 km/h from Northeast | Mostly Clear | Mostly Clear |
| September 18 | 60°F15°C | 87°F31°C | 4 mph6 km/h from Southeast | Mostly Clear | Mostly Clear |
| September 19 | 62°F17°C | 85°F29°C | 6 mph10 km/h from Southeast | Partly Cloudy | Mostly Cloudy |
| September 20 | 63°F17°C | 82°F28°C | 7 mph11 km/h from South | Partly Cloudy | Partly Cloudy |
| September 21 | 64°F18°C | 80°F26°C | 9 mph14 km/h from Southwest | Rain | Drizzle |
| September 22 | 63°F17°C | 80°F27°C | 9 mph14 km/h from Southwest | Thunderstorms | Mostly Cloudy |
Yes
Low of 58°F15°C, High of 86°F30°CWind: 4 mph7 km/h
Precipitation: None