Yes

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

Why? Because it's cold. simple as that.
36°F2°C & Mostly Cloudy

Wind is 2 mph4 km/h from the S, gusting to 6 mph10 km/h
April 24
11pm36°F2°C3 mph5 km/h SWMostly Cloudy
April 25
12am36°F2°C3 mph6 km/h SWCloudy
1am37°F3°C4 mph6 km/h SCloudy
2am39°F4°C4 mph7 km/h SWCloudy
3am42°F5°C5 mph7 km/h SWMostly Cloudy
4am45°F7°C6 mph10 km/h SWPartly Cloudy
5am49°F9°C7 mph11 km/h WPartly Cloudy
6am52°F11°C7 mph11 km/h WMostly Cloudy
7am52°F11°C9 mph14 km/h WMostly Cloudy
8am52°F11°C9 mph14 km/h WCloudy
9am53°F12°C8 mph13 km/h WCloudy
10am54°F12°C7 mph12 km/h WCloudy
DateLowHighWindDayNight
April 2436°F2°C54°F12°C7 mph11 km/h from WRainRain
April 2539°F4°C53°F12°C6 mph9 km/h from NECloudyDrizzle
April 2641°F5°C55°F13°C8 mph12 km/h from NERainRain
April 2744°F7°C54°F12°C10 mph16 km/h from WRainPartly Cloudy
April 2841°F5°C59°F15°C9 mph14 km/h from SMostly CloudyPartly Cloudy
April 2945°F7°C63°F17°C8 mph13 km/h from SEMostly CloudyMostly Cloudy
April 3050°F10°C67°F19°C9 mph14 km/h from NECloudyCloudy

Yes

Low of 39°F4°C, High of 53°F12°C
Wind: 6 mph9 km/h
Precipitation: None

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