Yes

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

Why? Because it's quite chilly.
50°F10°C & Partly Cloudy

Wind is 2 mph4 km/h from the E, gusting to 3 mph5 km/h
March 28
9am50°F10°C3 mph4 km/h EPartly Cloudy
10am50°F10°C2 mph4 km/h EMostly Cloudy
11am53°F11°C2 mph3 km/h NEMostly Cloudy
12pm56°F13°C2 mph4 km/h NWMostly Cloudy
1pm59°F15°C3 mph5 km/h WPartly Cloudy
2pm62°F17°C4 mph7 km/h WPartly Cloudy
3pm64°F18°C7 mph11 km/h WMostly Clear
4pm66°F19°C9 mph14 km/h WMostly Clear
5pm66°F19°C10 mph16 km/h WClear
6pm65°F19°C10 mph16 km/h WClear
7pm65°F18°C10 mph16 km/h WClear
8pm63°F17°C10 mph16 km/h WMostly Clear
DateLowHighWindDayNight
March 2848°F9°C66°F19°C7 mph11 km/h from WMostly ClearPartly Cloudy
March 2949°F9°C63°F17°C7 mph11 km/h from SWMostly ClearRain
March 3050°F10°C56°F14°C9 mph14 km/h from SRainDrizzle
March 3149°F10°C59°F15°C10 mph16 km/h from SRainDrizzle
April 147°F8°C65°F18°C6 mph9 km/h from WMostly ClearClear
April 247°F8°C71°F22°C5 mph8 km/h from WClearClear
April 350°F10°C76°F25°C5 mph8 km/h from WClearClear

Yes

Low of 48°F9°C, High of 63°F17°C
Wind: 7 mph11 km/h
Precipitation: None

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