Yes

you do need a jacket based on the weather in Guerneville, CA 95446, USA 1 second ago

Why? Because it's cold enough that makes you wish you had a hat, but you're still too proud to admit it!
46°F8°C & Clear

Wind is 3 mph5 km/h from the West, gusting to 4 mph6 km/h
October 28
3pm47°F8°C3 mph5 km/h WestClear
4pm51°F11°C2 mph4 km/h WestClear
5pm58°F15°C1 mph2 km/h SouthwestClear
6pm64°F18°C1 mph2 km/h SoutheastClear
7pm69°F21°C1 mph1 km/h SouthClear
8pm73°F23°C1 mph2 km/h SouthwestClear
9pm76°F24°C3 mph5 km/h SouthwestClear
10pm76°F25°C5 mph8 km/h SouthwestClear
11pm75°F24°C4 mph6 km/h SouthwestClear
October 29
12am73°F23°C4 mph6 km/h SouthwestClear
1am68°F20°C4 mph6 km/h SouthwestClear
2am63°F17°C4 mph6 km/h WestClear
DateLowHighWindDayNight
October 2846°F8°C76°F25°C3 mph4 km/h from SouthwestClearClear
October 2950°F10°C81°F27°C2 mph4 km/h from WestClearMostly Clear
October 3048°F9°C72°F22°C3 mph5 km/h from WestMostly CloudyMostly Clear
October 3146°F8°C76°F24°C3 mph4 km/h from WestMostly ClearMostly Clear
November 145°F7°C77°F25°C2 mph4 km/h from WestClearMostly Clear
November 250°F10°C77°F25°C2 mph4 km/h from SouthwestClearMostly Clear
November 349°F10°C69°F21°C3 mph5 km/h from SouthPartly CloudyMostly Cloudy

Yes

Low of 50°F10°C, High of 82°F28°C
Wind: 2 mph4 km/h
Precipitation: None

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