Yes

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

Why? Because too cold for just a hoodie, too warm for a parka!
48°F9°C & Partly Cloudy

Wind is 4 mph7 km/h from the West, gusting to 7 mph11 km/h
April 26
6am48°F9°C4 mph6 km/h WestPartly Cloudy
7am47°F9°C4 mph6 km/h WestMostly Clear
8am47°F8°C4 mph7 km/h WestPartly Cloudy
9am47°F9°C4 mph6 km/h WestPartly Cloudy
10am48°F9°C4 mph7 km/h WestPartly Cloudy
11am51°F10°C4 mph7 km/h NorthwestPartly Cloudy
12pm52°F11°C4 mph7 km/h NorthwestMostly Cloudy
1pm54°F12°C4 mph6 km/h WestPartly Cloudy
2pm56°F13°C5 mph7 km/h WestMostly Cloudy
3pm57°F14°C6 mph10 km/h WestMostly Cloudy
4pm57°F14°C8 mph13 km/h WestCloudy
5pm57°F14°C9 mph15 km/h WestCloudy
DateLowHighWindDayNight
April 2647°F8°C58°F14°C7 mph12 km/h from WestMostly CloudyDrizzle
April 2751°F10°C60°F15°C8 mph12 km/h from WestMostly CloudyMostly Clear
April 2850°F10°C65°F18°C7 mph11 km/h from WestMostly ClearPartly Cloudy
April 2951°F11°C64°F18°C6 mph10 km/h from SouthwestPartly CloudyPartly Cloudy
April 3052°F11°C66°F19°C7 mph12 km/h from WestMostly ClearMostly Cloudy
May 152°F11°C60°F15°C10 mph16 km/h from WestMostly CloudyCloudy
May 251°F10°C60°F15°C11 mph18 km/h from WestMostly CloudyMostly Cloudy

Yes

Low of 51°F11°C, High of 60°F16°C
Wind: 8 mph12 km/h
Precipitation: None

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