Yes

you do need a jacket based on the weather in Ann Arbor, MI, USA 1 second ago

Why? Because it's bitterly cold.
46°F8°C & Partly Cloudy

Wind is 7 mph11 km/h from the W, gusting to 14 mph23 km/h
April 19
10pm45°F7°C6 mph10 km/h WPartly Cloudy
11pm44°F7°C7 mph11 km/h SWMostly Clear
April 20
12am43°F6°C8 mph13 km/h WMostly Clear
1am42°F5°C9 mph14 km/h WPartly Cloudy
2am41°F5°C8 mph13 km/h WMostly Clear
3am39°F4°C9 mph15 km/h WMostly Clear
4am38°F3°C9 mph15 km/h WMostly Clear
5am36°F2°C9 mph15 km/h WMostly Clear
6am34°F1°C10 mph17 km/h WClear
7am33°F1°C10 mph17 km/h WMostly Clear
8am34°F1°C11 mph17 km/h WPartly Cloudy
9am36°F2°C14 mph22 km/h WPartly Cloudy
DateLowHighWindDayNight
April 1943°F6°C58°F14°C11 mph18 km/h from WPartly CloudyMostly Clear
April 2033°F1°C47°F9°C14 mph23 km/h from WMostly CloudyMostly Clear
April 2131°F-1°C55°F13°C12 mph20 km/h from WMostly ClearMostly Clear
April 2233°F1°C60°F16°C8 mph14 km/h from SWPartly CloudyMostly Cloudy
April 2344°F7°C60°F16°C15 mph24 km/h from SWDrizzleRain
April 2433°F1°C54°F12°C11 mph18 km/h from NPartly CloudyMostly Clear
April 2530°F-1°C55°F13°C8 mph13 km/h from NEMostly ClearPartly Cloudy

Yes

Low of 33°F1°C, High of 47°F9°C
Wind: 14 mph23 km/h
Precipitation: None

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