Yes

you do need a jacket based on the weather in Oxford St, London, UK 1 second ago

Why? Because it's cold. simple as that.
42°F6°C & Partly Cloudy

Wind is 1 mph2 km/h from the N, gusting to 5 mph8 km/h
April 24
6pm42°F6°C2 mph3 km/h NEPartly Cloudy
7pm41°F5°C2 mph3 km/h SEPartly Cloudy
8pm40°F4°C2 mph4 km/h SMostly Cloudy
9pm39°F4°C3 mph5 km/h SMostly Cloudy
10pm38°F3°C3 mph5 km/h SMostly Cloudy
11pm39°F4°C3 mph5 km/h SMostly Cloudy
April 25
12am39°F4°C4 mph6 km/h SMostly Cloudy
1am39°F4°C4 mph6 km/h SCloudy
2am41°F5°C4 mph7 km/h SCloudy
3am43°F6°C4 mph7 km/h SWMostly Cloudy
4am46°F8°C6 mph10 km/h SWMostly Cloudy
5am50°F10°C7 mph11 km/h WPartly Cloudy
DateLowHighWindDayNight
April 2341°F5°C50°F10°C6 mph10 km/h from NMostly CloudyMostly Cloudy
April 2438°F3°C54°F12°C7 mph11 km/h from WRainDrizzle
April 2540°F4°C53°F12°C5 mph8 km/h from NECloudyDrizzle
April 2642°F5°C57°F14°C7 mph11 km/h from NEDrizzleRain
April 2746°F8°C57°F14°C10 mph16 km/h from SWRainPartly Cloudy
April 2843°F6°C59°F15°C8 mph13 km/h from SMostly CloudyPartly Cloudy
April 2947°F8°C63°F17°C8 mph12 km/h from SEMostly CloudyMostly Cloudy

Yes

Low of 37°F3°C, High of 54°F12°C
Wind: 7 mph11 km/h
Precipitation: 39% rain

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