Yes

you do need a jacket based on the weather in Chalfont St Giles, Chalfont Saint Giles HP8, UK 1 second ago

Why? Because it's cool enough your breath is visible, but your nose isn’t red yet and the wind could blow a wig clean off your head!
49°F10°C & Cloudy

Wind is 11 mph18 km/h from the Southwest, gusting to 24 mph38 km/h
November 3
4am50°F10°C12 mph19 km/h SouthwestCloudy
5am51°F11°C12 mph20 km/h SouthwestMostly Cloudy
6am53°F11°C13 mph21 km/h SouthwestDrizzle
7am53°F12°C14 mph22 km/h SouthwestCloudy
8am54°F12°C15 mph23 km/h SouthwestCloudy
9am56°F13°C15 mph25 km/h SouthwestWindy
10am57°F14°C15 mph25 km/h SouthwestWindy
11am58°F14°C17 mph27 km/h SouthwestWindy
12pm59°F15°C17 mph27 km/h SouthwestWindy
1pm59°F15°C17 mph28 km/h SouthwestWindy
2pm59°F15°C16 mph26 km/h SouthwestWindy
3pm59°F15°C15 mph25 km/h SouthwestWindy
DateLowHighWindDayNight
November 343°F6°C59°F15°C16 mph25 km/h from SouthwestWindyCloudy
November 455°F13°C59°F15°C13 mph22 km/h from SouthCloudyCloudy
November 556°F13°C61°F16°C10 mph16 km/h from SouthDrizzleCloudy
November 647°F8°C59°F15°C9 mph15 km/h from SouthCloudyMostly Clear
November 746°F8°C57°F14°C12 mph20 km/h from SouthDrizzleDrizzle
November 845°F7°C58°F14°C5 mph8 km/h from WestPartly CloudyPartly Cloudy
November 943°F6°C57°F14°C6 mph10 km/h from SouthMostly CloudyMostly Cloudy

Yes

Low of 55°F13°C, High of 59°F15°C
Wind: 13 mph22 km/h
Precipitation: None

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