Yes

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

Why? Because it's cold. simple as that.
37°F3°C & Mostly Cloudy

Wind is 4 mph7 km/h from the SW, gusting to 10 mph16 km/h
April 25
1am37°F3°C5 mph8 km/h SWCloudy
2am40°F4°C5 mph8 km/h SCloudy
3am43°F6°C6 mph9 km/h SCloudy
4am45°F7°C7 mph11 km/h SWCloudy
5am48°F9°C9 mph15 km/h SWCloudy
6am51°F10°C9 mph15 km/h WMostly Cloudy
7am53°F12°C9 mph15 km/h WMostly Cloudy
8am54°F12°C9 mph15 km/h WCloudy
9am54°F12°C10 mph16 km/h WCloudy
10am53°F12°C9 mph14 km/h WCloudy
11am52°F11°C8 mph13 km/h WCloudy
12pm51°F11°C8 mph13 km/h WCloudy
DateLowHighWindDayNight
April 2436°F2°C54°F12°C8 mph13 km/h from WRainRain
April 2540°F4°C51°F11°C7 mph10 km/h from NECloudyRain
April 2643°F6°C55°F13°C8 mph13 km/h from EDrizzleRain
April 2745°F7°C56°F13°C13 mph21 km/h from SWDrizzlePartly Cloudy
April 2842°F6°C58°F14°C10 mph15 km/h from SMostly CloudyPartly Cloudy
April 2945°F7°C59°F15°C8 mph14 km/h from SECloudyCloudy
April 3050°F10°C64°F18°C8 mph13 km/h from NEMostly CloudyMostly Cloudy

Yes

Low of 40°F5°C, High of 51°F11°C
Wind: 7 mph10 km/h
Precipitation: None

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