Yes

you do need a jacket based on the weather in London WC1A, UK 1 second ago

Why? Because it's bitterly cold.
41°F5°C & Clear

Wind is 7 mph12 km/h from the N, gusting to 19 mph31 km/h
April 19
10pm40°F5°C7 mph12 km/h NMostly Clear
11pm39°F4°C7 mph11 km/h NMostly Clear
April 20
12am39°F4°C7 mph11 km/h NMostly Clear
1am38°F3°C7 mph11 km/h NMostly Clear
2am39°F4°C7 mph11 km/h NWMostly Clear
3am41°F5°C8 mph13 km/h NMostly Clear
4am44°F7°C9 mph15 km/h NPartly Cloudy
5am46°F8°C11 mph18 km/h NMostly Cloudy
6am48°F9°C11 mph18 km/h NMostly Cloudy
7am49°F10°C11 mph18 km/h NMostly Cloudy
8am50°F10°C10 mph17 km/h NCloudy
9am51°F10°C10 mph16 km/h NMostly Cloudy
DateLowHighWindDayNight
April 1938°F3°C52°F11°C10 mph16 km/h from NMostly CloudyPartly Cloudy
April 2038°F3°C54°F12°C10 mph17 km/h from NMostly CloudyMostly Clear
April 2137°F3°C52°F11°C6 mph9 km/h from NWDrizzleDrizzle
April 2240°F5°C52°F11°C11 mph18 km/h from NMostly CloudyMostly Cloudy
April 2337°F3°C53°F12°C7 mph12 km/h from NWMostly CloudyMostly Cloudy
April 2441°F5°C54°F12°C6 mph10 km/h from WMostly CloudyMostly Cloudy
April 2542°F5°C57°F14°C6 mph10 km/h from SWMostly CloudyMostly Cloudy

Yes

Low of 38°F4°C, High of 54°F12°C
Wind: 10 mph17 km/h
Precipitation: None

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