Yes

you do need a jacket based on the weather in San Diego, CA 92126, USA 16 minutes ago

Why? Because it's cool enough your breath is visible, but your nose isn’t red yet!
50°F10°C & Mostly Cloudy

Wind is 3 mph5 km/h from the East, gusting to 4 mph7 km/h
December 23
9am49°F10°C3 mph5 km/h EastPartly Cloudy
10am48°F9°C3 mph4 km/h EastPartly Cloudy
11am52°F11°C2 mph4 km/h EastMostly Clear
12pm57°F14°C2 mph2 km/h NorthMostly Clear
1pm62°F17°C2 mph3 km/h NorthwestPartly Cloudy
2pm65°F19°C4 mph7 km/h WestMostly Clear
3pm68°F20°C5 mph9 km/h WestMostly Clear
4pm70°F21°C6 mph9 km/h WestClear
5pm69°F20°C6 mph10 km/h WestMostly Clear
6pm67°F19°C6 mph10 km/h WestPartly Cloudy
7pm64°F18°C5 mph9 km/h NorthwestPartly Cloudy
8pm61°F16°C4 mph7 km/h NorthwestMostly Cloudy
DateLowHighWindDayNight
December 2348°F9°C70°F21°C4 mph7 km/h from NorthwestPartly CloudyMostly Cloudy
December 2449°F9°C63°F17°C5 mph8 km/h from SouthwestMostly CloudyPartly Cloudy
December 2548°F9°C64°F18°C4 mph7 km/h from WestMostly ClearMostly Cloudy
December 2643°F6°C66°F19°C3 mph6 km/h from WestPartly CloudyPartly Cloudy
December 2745°F7°C65°F19°C4 mph6 km/h from WestMostly CloudyMostly Cloudy
December 2852°F11°C67°F19°C3 mph6 km/h from NorthwestMostly CloudyMostly Cloudy
December 2950°F10°C67°F19°C4 mph6 km/h from NorthwestPartly CloudyMostly Cloudy

Yes

Low of 49°F10°C, High of 64°F18°C
Wind: 5 mph8 km/h
Precipitation: None

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