No

you don't need a jacket based on the weather in Oswego, IL, USA 12 minutes ago

81°F27°C & Clear

Wind is 6 mph9 km/h from the West, gusting to 10 mph16 km/h
September 26
5pm81°F27°C6 mph9 km/h WestClear
6pm81°F27°C5 mph9 km/h SouthwestClear
7pm78°F26°C4 mph7 km/h SouthwestClear
8pm74°F23°C6 mph9 km/h SouthClear
9pm71°F22°C5 mph9 km/h SouthClear
10pm69°F20°C6 mph9 km/h SouthClear
11pm67°F19°C6 mph9 km/h SouthClear
September 27
12am65°F18°C6 mph9 km/h SouthClear
1am63°F17°C6 mph9 km/h SouthwestClear
2am62°F17°C5 mph9 km/h SouthwestClear
3am61°F16°C5 mph8 km/h SouthwestClear
4am60°F15°C5 mph8 km/h SouthwestClear
DateLowHighWindDayNight
September 2651°F11°C81°F27°C4 mph6 km/h from SouthwestClearClear
September 2756°F13°C84°F29°C7 mph11 km/h from SouthwestClearClear
September 2858°F14°C84°F29°C4 mph6 km/h from SouthMostly ClearClear
September 2958°F14°C84°F29°C3 mph5 km/h from SouthClearMostly Clear
September 3059°F15°C82°F28°C7 mph11 km/h from NortheastPartly CloudyMostly Cloudy
October 160°F16°C78°F26°C9 mph14 km/h from EastMostly CloudyPartly Cloudy
October 255°F13°C76°F25°C7 mph12 km/h from EastPartly CloudyClear

Yes

Low of 56°F14°C, High of 83°F29°C
Wind: 7 mph11 km/h
Precipitation: None

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