Yes
you do need a jacket based on the weather in Crystal Lake, IL, USA 1 second ago
Why? Because just cool enough for a jacket, but not warm enough to ditch it!
58°F15°C & Mostly Cloudy
Wind is 6 mph10 km/h from the West, gusting to 14 mph23 km/h
| September 6 | ||||
| 9pm | 57°F14°C | 5 mph8 km/h Northwest | Cloudy | |
| 10pm | 55°F13°C | 6 mph9 km/h Northwest | Partly Cloudy | |
| 11pm | 53°F11°C | 6 mph9 km/h Northwest | Mostly Clear | |
| September 7 | ||||
| 12am | 51°F10°C | 5 mph8 km/h West | Mostly Clear | |
| 1am | 50°F10°C | 5 mph7 km/h Northwest | Clear | |
| 2am | 48°F9°C | 5 mph8 km/h West | Clear | |
| 3am | 47°F8°C | 5 mph8 km/h West | Clear | |
| 4am | 46°F8°C | 5 mph9 km/h West | Clear | |
| 5am | 45°F7°C | 6 mph9 km/h West | Clear | |
| 6am | 44°F7°C | 6 mph9 km/h Northwest | Clear | |
| 7am | 44°F7°C | 6 mph9 km/h Northwest | Clear | |
| 8am | 44°F7°C | 6 mph9 km/h Northwest | Clear | |
| Date | Low | High | Wind | Day | Night |
|---|---|---|---|---|---|
| September 6 | 45°F7°C | 64°F18°C | 6 mph10 km/h from West | Mostly Clear | Mostly Clear |
| September 7 | 44°F7°C | 65°F18°C | 8 mph13 km/h from Northwest | Mostly Clear | Clear |
| September 8 | 45°F7°C | 70°F21°C | 7 mph12 km/h from South | Clear | Partly Cloudy |
| September 9 | 51°F11°C | 72°F22°C | 9 mph15 km/h from South | Partly Cloudy | Mostly Cloudy |
| September 10 | 58°F14°C | 75°F24°C | 4 mph7 km/h from Southwest | Partly Cloudy | Partly Cloudy |
| September 11 | 58°F14°C | 77°F25°C | 7 mph11 km/h from Northeast | Mostly Clear | Mostly Clear |
| September 12 | 59°F15°C | 80°F27°C | 6 mph10 km/h from South | Mostly Clear | Partly Cloudy |
Yes
Low of 44°F7°C, High of 65°F19°CWind: 8 mph13 km/h
Precipitation: None