Yes

you do need a jacket based on the weather in Salt Lake City, UT 84120, USA 1 second ago

Why? Because it's cold. simple as that.
47°F8°C & Rain

Wind is 4 mph6 km/h from the W, gusting to 9 mph15 km/h
April 27
12am47°F8°C4 mph7 km/h WRain
1am46°F8°C4 mph6 km/h WCloudy
2am46°F8°C4 mph6 km/h WRain
3am46°F8°C3 mph6 km/h WRain
4am45°F7°C4 mph6 km/h SWRain
5am45°F7°C4 mph7 km/h SWRain
6am44°F7°C4 mph7 km/h WRain
7am44°F6°C3 mph5 km/h WRain
8am43°F6°C4 mph6 km/h WDrizzle
9am44°F6°C5 mph8 km/h NWCloudy
10am44°F7°C5 mph8 km/h WCloudy
11am45°F7°C6 mph9 km/h WCloudy
DateLowHighWindDayNight
April 2646°F8°C52°F11°C3 mph6 km/h from NWRainRain
April 2743°F6°C52°F11°C7 mph11 km/h from NWDrizzleMostly Cloudy
April 2843°F6°C61°F16°C6 mph9 km/h from NWPartly CloudyMostly Clear
April 2946°F8°C70°F21°C10 mph16 km/h from SWPartly CloudyMostly Clear
April 3044°F7°C63°F17°C6 mph9 km/h from WMostly ClearPartly Cloudy
May 141°F5°C59°F15°C10 mph15 km/h from NWMostly ClearPartly Cloudy
May 235°F1°C60°F16°C4 mph7 km/h from NPartly CloudyPartly Cloudy

Yes

Low of 43°F6°C, High of 52°F11°C
Wind: 7 mph11 km/h
Precipitation: 55% rain

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