Yes

you do need a jacket based on the weather in San Diego (La Jolla), California, United States 1 second ago

Why? Because it's not very warm out!
55°F13°C & Mostly Cloudy

Wind is 4 mph7 km/h from the Southeast, gusting to 6 mph10 km/h
April 16
10am55°F13°C5 mph8 km/h SoutheastMostly Cloudy
11am56°F14°C5 mph8 km/h SoutheastCloudy
12pm57°F14°C5 mph7 km/h SouthMostly Cloudy
1pm57°F14°C5 mph9 km/h SouthwestMostly Cloudy
2pm58°F15°C6 mph10 km/h SouthMostly Cloudy
3pm59°F15°C5 mph8 km/h SouthwestMostly Cloudy
4pm60°F15°C5 mph9 km/h SouthwestMostly Cloudy
5pm62°F16°C7 mph11 km/h WestPartly Cloudy
6pm62°F17°C8 mph13 km/h WestPartly Cloudy
7pm62°F17°C8 mph13 km/h WestMostly Clear
8pm61°F16°C8 mph12 km/h WestMostly Clear
9pm61°F16°C7 mph12 km/h WestMostly Clear
DateLowHighWindDayNight
April 1655°F13°C62°F17°C6 mph10 km/h from SouthwestPartly CloudyMostly Cloudy
April 1755°F13°C63°F17°C7 mph11 km/h from WestPartly CloudyMostly Cloudy
April 1855°F13°C61°F16°C8 mph14 km/h from WestMostly CloudyPartly Cloudy
April 1953°F12°C65°F19°C8 mph13 km/h from NorthwestClearMostly Clear
April 2053°F12°C66°F19°C7 mph12 km/h from NorthwestPartly CloudyMostly Cloudy
April 2153°F12°C65°F18°C7 mph11 km/h from WestMostly ClearPartly Cloudy
April 2254°F12°C65°F18°C6 mph10 km/h from WestMostly ClearPartly Cloudy

Yes

Low of 55°F13°C, High of 64°F18°C
Wind: 7 mph11 km/h
Precipitation: 15% rain

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