Yes

you do need a jacket based on the weather in Belfast, UK 1 second ago

Why? Because rain's coming down and it's not very warm out!
58°F14°C & Rain

Wind is 7 mph11 km/h from the North, gusting to 15 mph24 km/h
June 14
6am58°F14°C8 mph12 km/h NorthRain
7am58°F15°C7 mph11 km/h NorthwestRain
8am58°F15°C7 mph12 km/h NorthwestRain
9am59°F15°C8 mph14 km/h NorthwestRain
10am59°F15°C9 mph14 km/h NorthwestRain
11am60°F15°C9 mph15 km/h NorthwestRain
12pm60°F16°C8 mph14 km/h NorthwestDrizzle
1pm60°F16°C8 mph12 km/h NorthwestDrizzle
2pm60°F16°C7 mph11 km/h WestDrizzle
3pm59°F15°C8 mph12 km/h WestCloudy
4pm58°F15°C6 mph10 km/h WestCloudy
5pm57°F14°C6 mph10 km/h WestMostly Cloudy
DateLowHighWindDayNight
June 1355°F13°C60°F16°C7 mph12 km/h from NorthwestRainDrizzle
June 1450°F10°C65°F18°C11 mph17 km/h from WestMostly CloudyPartly Cloudy
June 1554°F12°C69°F20°C11 mph18 km/h from SouthwestCloudyMostly Cloudy
June 1654°F12°C68°F20°C11 mph17 km/h from WestPartly CloudyPartly Cloudy
June 1750°F10°C67°F19°C5 mph9 km/h from WestMostly CloudyPartly Cloudy
June 1852°F11°C71°F22°C11 mph18 km/h from SoutheastPartly CloudyPartly Cloudy
June 1955°F13°C70°F21°C10 mph16 km/h from WestMostly CloudyMostly Cloudy

Yes

Low of 50°F10°C, High of 64°F18°C
Wind: 11 mph17 km/h
Precipitation: 14% rain

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