Yes

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

Why? Because it's not very warm out and it's on the windy side!
52°F11°C & Cloudy

Wind is 12 mph19 km/h from the Southwest, gusting to 24 mph39 km/h
June 3
12am52°F11°C12 mph19 km/h SouthwestCloudy
1am53°F12°C13 mph21 km/h SouthwestCloudy
2am55°F13°C15 mph24 km/h SouthwestCloudy
3am57°F14°C17 mph27 km/h SouthwestWindy
4am58°F15°C18 mph29 km/h SouthwestWindy
5am58°F14°C18 mph29 km/h SouthwestWindy
6am57°F14°C18 mph30 km/h SouthwestDrizzle
7am58°F14°C19 mph30 km/h SouthwestWindy
8am59°F15°C19 mph30 km/h SouthwestDrizzle
9am60°F16°C18 mph30 km/h SouthwestWindy
10am61°F16°C17 mph28 km/h SouthwestDrizzle
11am61°F16°C16 mph26 km/h SouthwestWindy
DateLowHighWindDayNight
June 251°F11°C62°F17°C17 mph27 km/h from SouthwestDrizzlePartly Cloudy
June 350°F10°C64°F18°C12 mph20 km/h from SouthwestMostly CloudyDrizzle
June 451°F11°C63°F17°C12 mph20 km/h from SouthwestRainDrizzle
June 551°F11°C65°F18°C12 mph19 km/h from SouthwestDrizzleDrizzle
June 651°F11°C61°F16°C15 mph25 km/h from SouthwestRainDrizzle
June 748°F9°C62°F17°C13 mph21 km/h from WestPartly CloudyPartly Cloudy
June 847°F8°C66°F19°C8 mph13 km/h from WestMostly CloudyMostly Cloudy

Yes

Low of 49°F10°C, High of 64°F18°C
Wind: 12 mph20 km/h
Precipitation: 12% rain

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