Yes

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

Why? Because heavy rain out there and it's fairly windy outside!
60°F15°C & Heavy Rain

Wind is 9 mph14 km/h from the South, gusting to 22 mph35 km/h
September 4
4am61°F16°C10 mph16 km/h SouthwestRain
5am62°F17°C10 mph16 km/h SouthwestPartly Cloudy
6am64°F18°C11 mph17 km/h SouthwestPartly Cloudy
7am64°F18°C11 mph18 km/h SouthwestPartly Cloudy
8am65°F19°C11 mph18 km/h SouthwestMostly Cloudy
9am67°F20°C11 mph18 km/h SouthwestPartly Cloudy
10am68°F20°C11 mph18 km/h SouthwestPartly Cloudy
11am67°F20°C12 mph19 km/h WestPartly Cloudy
12pm67°F19°C12 mph19 km/h WestMostly Clear
1pm66°F19°C10 mph16 km/h WestMostly Clear
2pm64°F18°C8 mph12 km/h WestMostly Clear
3pm63°F17°C6 mph10 km/h WestClear
DateLowHighWindDayNight
September 357°F14°C68°F20°C10 mph17 km/h from SouthwestRainClear
September 454°F12°C70°F21°C5 mph9 km/h from WestPartly CloudyMostly Cloudy
September 554°F12°C71°F22°C7 mph12 km/h from SoutheastMostly CloudyMostly Cloudy
September 662°F17°C71°F21°C8 mph13 km/h from SouthDrizzleMostly Clear
September 756°F14°C68°F20°C10 mph17 km/h from SouthPartly CloudyPartly Cloudy
September 857°F14°C66°F19°C10 mph16 km/h from SouthPartly CloudyRain
September 956°F13°C64°F18°C12 mph19 km/h from SouthDrizzleMostly Cloudy

Yes

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

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