Yes

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

Why? Because a little drizzle out!
67°F19°C & Drizzle

Wind is 4 mph7 km/h from the Southwest, gusting to 9 mph15 km/h
June 27
8pm67°F19°C5 mph7 km/h SouthwestDrizzle
9pm67°F19°C4 mph6 km/h SouthwestCloudy
10pm66°F19°C3 mph4 km/h WestMostly Cloudy
11pm64°F18°C4 mph7 km/h NorthwestPartly Cloudy
June 28
12am61°F16°C4 mph7 km/h NorthwestPartly Cloudy
1am59°F15°C4 mph6 km/h NorthwestPartly Cloudy
2am57°F14°C3 mph5 km/h WestMostly Cloudy
3am57°F14°C3 mph4 km/h NorthwestMostly Cloudy
4am57°F14°C2 mph3 km/h NorthwestMostly Cloudy
5am56°F13°C1 mph2 km/h NorthwestMostly Cloudy
6am56°F13°C1 mph2 km/h NorthCloudy
7am56°F13°C1 mph2 km/h NortheastCloudy
DateLowHighWindDayNight
June 2755°F13°C67°F20°C3 mph5 km/h from SouthwestDrizzleMostly Cloudy
June 2856°F13°C72°F22°C4 mph6 km/h from NorthPartly CloudyClear
June 2955°F13°C77°F25°C10 mph15 km/h from NorthClearClear
June 3059°F15°C81°F27°C8 mph13 km/h from NorthClearClear
July 159°F15°C81°F27°C6 mph9 km/h from NorthClearClear
July 258°F14°C76°F25°C5 mph8 km/h from NorthwestMostly ClearMostly Cloudy
July 355°F13°C73°F23°C5 mph7 km/h from WestPartly CloudyPartly Cloudy

Yes

Low of 55°F13°C, High of 72°F22°C
Wind: 4 mph6 km/h
Precipitation: 3% rain

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