Yes

you do need a jacket based on the weather in Seattle, WA 98122, USA 1 second ago

Why? Because it's not very warm out.
51°F10°C & Cloudy

Wind is 8 mph13 km/h from the S, gusting to 16 mph25 km/h
April 24
1pm51°F10°C8 mph13 km/h SCloudy
2pm52°F11°C8 mph13 km/h SCloudy
3pm54°F12°C9 mph14 km/h SCloudy
4pm54°F12°C9 mph14 km/h SDrizzle
5pm55°F13°C9 mph14 km/h SDrizzle
6pm56°F13°C8 mph13 km/h SWCloudy
7pm56°F14°C8 mph12 km/h SWCloudy
8pm56°F13°C7 mph12 km/h SWDrizzle
9pm54°F12°C7 mph11 km/h SWCloudy
10pm53°F12°C6 mph10 km/h SWDrizzle
11pm52°F11°C6 mph9 km/h SWCloudy
April 25
12am50°F10°C5 mph7 km/h SWMostly Cloudy
DateLowHighWindDayNight
April 2446°F8°C56°F14°C8 mph13 km/h from SDrizzleDrizzle
April 2547°F8°C54°F12°C8 mph13 km/h from SRainDrizzle
April 2648°F9°C58°F15°C7 mph10 km/h from SDrizzleDrizzle
April 2748°F9°C57°F14°C10 mph17 km/h from SCloudyDrizzle
April 2848°F9°C57°F14°C11 mph17 km/h from SWDrizzleMostly Cloudy
April 2945°F7°C56°F13°C11 mph17 km/h from SWPartly CloudyPartly Cloudy
April 3042°F6°C56°F14°C7 mph11 km/h from SMostly CloudyMostly Cloudy

Yes

Low of 47°F9°C, High of 54°F12°C
Wind: 8 mph13 km/h
Precipitation: 90% rain

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