Yes

you do need a jacket based on the weather in Ketchikan, AK 99901, USA 11 minutes ago

Why? Because it's pretty chilly and it's fairly windy outside!
53°F11°C & Cloudy

Wind is 11 mph18 km/h from the Southeast, gusting to 22 mph36 km/h
September 15
6am53°F12°C12 mph19 km/h SoutheastDrizzle
7am53°F12°C13 mph20 km/h SoutheastDrizzle
8am52°F11°C14 mph22 km/h SoutheastRain
9am52°F11°C15 mph24 km/h SoutheastRain
10am51°F11°C15 mph25 km/h SoutheastRain
11am51°F10°C15 mph24 km/h SoutheastRain
12pm51°F11°C15 mph25 km/h SoutheastRain
1pm52°F11°C15 mph24 km/h SoutheastRain
2pm53°F12°C15 mph24 km/h SoutheastRain
3pm54°F12°C14 mph23 km/h SoutheastRain
4pm55°F13°C15 mph24 km/h SoutheastRain
5pm55°F13°C15 mph24 km/h SoutheastRain
DateLowHighWindDayNight
September 1551°F10°C57°F14°C14 mph22 km/h from SoutheastRainRain
September 1654°F12°C68°F20°C7 mph11 km/h from SoutheastPartly CloudyRain
September 1751°F11°C58°F14°C9 mph15 km/h from SouthRainDrizzle
September 1850°F10°C55°F13°C9 mph14 km/h from SoutheastRainRain
September 1954°F12°C59°F15°C9 mph14 km/h from SoutheastRainRain
September 2052°F11°C57°F14°C13 mph20 km/h from SouthThunderstormsThunderstorms
September 2151°F10°C56°F13°C9 mph14 km/h from SouthThunderstormsThunderstorms

Yes

Low of 55°F13°C, High of 68°F20°C
Wind: 7 mph11 km/h
Precipitation: None

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