Yes

you do need a jacket based on the weather in Joliet, IL, USA 1 second ago

Why? Because it's quite chilly.
50°F10°C & Cloudy

Wind is 9 mph15 km/h from the N, gusting to 18 mph29 km/h
April 19
12am50°F10°C9 mph15 km/h NDrizzle
1am49°F10°C9 mph14 km/h NCloudy
2am49°F10°C9 mph15 km/h NMostly Cloudy
3am48°F9°C11 mph17 km/h NWMostly Cloudy
4am47°F8°C13 mph20 km/h NWPartly Cloudy
5am44°F7°C13 mph21 km/h NWMostly Clear
6am42°F6°C12 mph20 km/h NWClear
7am40°F4°C11 mph17 km/h NWClear
8am40°F4°C9 mph15 km/h NWClear
9am42°F6°C10 mph16 km/h NWClear
10am45°F7°C11 mph18 km/h NWClear
11am47°F8°C13 mph21 km/h NWClear
DateLowHighWindDayNight
April 1844°F7°C64°F18°C5 mph7 km/h from ECloudyRain
April 1940°F4°C57°F14°C14 mph22 km/h from WMostly ClearMostly Clear
April 2034°F1°C50°F10°C13 mph21 km/h from NWPartly CloudyPartly Cloudy
April 2135°F1°C59°F15°C9 mph15 km/h from WMostly ClearMostly Clear
April 2238°F3°C64°F18°C9 mph14 km/h from SWPartly CloudyCloudy
April 2349°F9°C67°F20°C14 mph23 km/h from WMostly CloudyPartly Cloudy
April 2440°F4°C57°F14°C11 mph18 km/h from NEMostly ClearPartly Cloudy

Yes

Low of 39°F4°C, High of 57°F14°C
Wind: 14 mph22 km/h
Precipitation: None

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