Yes

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

Why? Because it's not very warm out.
54°F12°C & Cloudy

Wind is 7 mph12 km/h from the W, gusting to 13 mph21 km/h
April 25
12pm54°F12°C8 mph13 km/h WCloudy
1pm55°F13°C9 mph15 km/h WCloudy
2pm56°F13°C10 mph16 km/h WCloudy
3pm57°F14°C11 mph18 km/h WMostly Cloudy
4pm58°F14°C12 mph20 km/h WMostly Cloudy
5pm59°F15°C13 mph21 km/h WPartly Cloudy
6pm58°F15°C13 mph22 km/h WPartly Cloudy
7pm58°F15°C13 mph21 km/h WPartly Cloudy
8pm58°F14°C13 mph21 km/h WMostly Cloudy
9pm57°F14°C13 mph20 km/h WMostly Cloudy
10pm56°F13°C11 mph17 km/h WMostly Cloudy
11pm55°F13°C10 mph15 km/h WMostly Cloudy
DateLowHighWindDayNight
April 2551°F11°C59°F15°C11 mph18 km/h from WMostly CloudyCloudy
April 2652°F11°C59°F15°C13 mph21 km/h from WMostly CloudyPartly Cloudy
April 2750°F10°C59°F15°C10 mph15 km/h from WPartly CloudyMostly Clear
April 2850°F10°C61°F16°C9 mph14 km/h from WPartly CloudyMostly Clear
April 2949°F10°C61°F16°C7 mph11 km/h from WMostly ClearMostly Clear
April 3049°F9°C63°F17°C5 mph9 km/h from NWMostly ClearMostly Clear
May 149°F9°C61°F16°C7 mph11 km/h from WMostly ClearMostly Clear

Yes

Low of 52°F11°C, High of 59°F15°C
Wind: 13 mph21 km/h
Precipitation: 15% rain

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