Yes

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

Why? Because it's cold. simple as that.
44°F7°C & Drizzle

Wind is 7 mph12 km/h from the E, gusting to 16 mph26 km/h
April 26
8pm44°F7°C8 mph13 km/h EDrizzle
9pm44°F6°C9 mph14 km/h NERain
10pm43°F6°C9 mph15 km/h NERain
11pm43°F6°C10 mph16 km/h NERain
April 27
12am42°F6°C10 mph16 km/h NEDrizzle
1am43°F6°C9 mph15 km/h NEDrizzle
2am43°F6°C9 mph14 km/h NECloudy
3am44°F7°C8 mph13 km/h NECloudy
4am45°F7°C7 mph12 km/h NECloudy
5am48°F9°C7 mph11 km/h ECloudy
6am50°F10°C6 mph9 km/h ECloudy
7am52°F11°C6 mph9 km/h ECloudy
DateLowHighWindDayNight
April 2642°F6°C56°F13°C7 mph11 km/h from EDrizzleRain
April 2744°F7°C53°F12°C12 mph20 km/h from SWDrizzleMostly Clear
April 2840°F5°C59°F15°C10 mph15 km/h from SPartly CloudyMostly Clear
April 2945°F7°C62°F17°C9 mph15 km/h from SEMostly CloudyMostly Cloudy
April 3048°F9°C65°F18°C5 mph8 km/h from SEDrizzleCloudy
May 149°F9°C60°F16°C9 mph14 km/h from NWDrizzlePartly Cloudy
May 247°F8°C64°F18°C10 mph16 km/h from NMostly ClearMostly Cloudy

Yes

Low of 45°F7°C, High of 54°F12°C
Wind: 12 mph20 km/h
Precipitation: 58% rain

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