Yes

you do need a jacket based on the weather in Central London, London WC2N 5DU, UK 25 minutes ago

Why? Because it's not very warm out!
59°F15°C & Cloudy

Wind is 6 mph10 km/h from the South, gusting to 17 mph27 km/h
September 4
3am60°F15°C9 mph14 km/h SouthRain
4am61°F16°C10 mph15 km/h SouthwestDrizzle
5am62°F17°C10 mph16 km/h SouthwestPartly Cloudy
6am63°F17°C10 mph17 km/h SouthwestPartly Cloudy
7am64°F18°C11 mph18 km/h SouthwestMostly Cloudy
8am66°F19°C11 mph17 km/h SouthwestMostly Cloudy
9am67°F20°C11 mph17 km/h SouthwestPartly Cloudy
10am68°F20°C10 mph17 km/h SouthwestPartly Cloudy
11am68°F20°C11 mph17 km/h WestPartly Cloudy
12pm67°F19°C11 mph18 km/h WestMostly Clear
1pm66°F19°C10 mph16 km/h WestMostly Clear
2pm64°F18°C8 mph13 km/h WestMostly Clear
DateLowHighWindDayNight
September 358°F14°C68°F20°C10 mph16 km/h from SouthwestRainClear
September 454°F12°C70°F21°C5 mph9 km/h from WestMostly ClearMostly Cloudy
September 554°F12°C71°F22°C7 mph12 km/h from SoutheastMostly CloudyMostly Cloudy
September 662°F17°C72°F22°C8 mph12 km/h from SouthDrizzleMostly Clear
September 758°F14°C69°F21°C10 mph16 km/h from SouthPartly CloudyPartly Cloudy
September 857°F14°C67°F19°C9 mph15 km/h from SouthPartly CloudyMostly Clear
September 956°F14°C66°F19°C11 mph18 km/h from SouthRainPartly Cloudy

Yes

Low of 55°F13°C, High of 70°F21°C
Wind: 5 mph9 km/h
Precipitation: None

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