Yes

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

Why? Because just cool enough for a jacket, but not warm enough to ditch it!
57°F14°C & Partly Cloudy

Wind is 11 mph17 km/h from the Southwest, gusting to 17 mph28 km/h
April 23
11pm57°F14°C11 mph17 km/h SouthwestMostly Clear
April 24
12am55°F13°C10 mph16 km/h SouthwestMostly Clear
1am53°F12°C9 mph14 km/h SouthwestPartly Cloudy
2am53°F12°C8 mph14 km/h SouthwestPartly Cloudy
3am52°F11°C9 mph14 km/h SouthwestPartly Cloudy
4am51°F11°C8 mph13 km/h SouthwestPartly Cloudy
5am51°F10°C8 mph12 km/h SouthwestMostly Cloudy
6am51°F10°C8 mph12 km/h SouthwestCloudy
7am51°F10°C7 mph12 km/h SouthwestCloudy
8am50°F10°C7 mph11 km/h SouthwestCloudy
9am50°F10°C7 mph11 km/h SouthwestCloudy
10am51°F10°C7 mph12 km/h SouthwestCloudy
DateLowHighWindDayNight
April 2350°F10°C62°F16°C10 mph16 km/h from SouthwestMostly ClearPartly Cloudy
April 2450°F10°C63°F17°C10 mph15 km/h from SouthwestCloudyCloudy
April 2550°F10°C60°F16°C10 mph16 km/h from SouthwestMostly CloudyPartly Cloudy
April 2647°F8°C63°F17°C8 mph12 km/h from SouthwestMostly CloudyMostly Cloudy
April 2750°F10°C64°F18°C5 mph7 km/h from SouthwestMostly CloudyMostly Clear
April 2851°F10°C73°F23°C6 mph10 km/h from WestMostly ClearMostly Clear
April 2953°F12°C74°F23°C6 mph9 km/h from SouthwestPartly CloudyMostly Clear

Yes

Low of 50°F10°C, High of 64°F18°C
Wind: 10 mph15 km/h
Precipitation: None

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