Yes

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

Why? Because it's colder than a polar bear's pyjamas
31°F-0°C & Partly Cloudy

Wind is 6 mph10 km/h from the S, gusting to 12 mph19 km/h
December 2
1pm31°F-1°C7 mph11 km/h SPartly Cloudy
2pm32°F-0°C7 mph11 km/h SEMostly Cloudy
3pm33°F1°C7 mph12 km/h SECloudy
4pm34°F1°C7 mph12 km/h SECloudy
5pm35°F2°C8 mph12 km/h SECloudy
6pm37°F3°C8 mph14 km/h SDrizzle
7pm38°F3°C9 mph15 km/h SDrizzle
8pm39°F4°C9 mph14 km/h SDrizzle
9pm40°F4°C8 mph12 km/h SRain
10pm40°F4°C6 mph10 km/h SDrizzle
11pm39°F4°C5 mph8 km/h SCloudy
December 3
12am39°F4°C4 mph7 km/h SCloudy
DateLowHighWindDayNight
December 127°F-3°C38°F3°C4 mph6 km/h from SPartly CloudyFreezingrain
December 238°F3°C44°F7°C5 mph8 km/h from SERainRain
December 337°F3°C45°F7°C14 mph22 km/h from NRainMostly Cloudy
December 434°F1°C44°F7°C8 mph13 km/h from NWPartly CloudyPartly Cloudy
December 532°F-0°C44°F7°C12 mph20 km/h from SERainRain
December 642°F6°C50°F10°C16 mph26 km/h from SERainDrizzle
December 746°F8°C51°F11°C10 mph16 km/h from SPartly CloudyMostly Cloudy

Yes

Low of 38°F4°C, High of 44°F7°C
Wind: 5 mph8 km/h
Precipitation: 78% rain

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