Yes

you do need a jacket based on the weather in Osaka, Osaka Prefecture, Japan 1 second ago

Why? Because just cool enough for a jacket, but not warm enough to ditch it!
53°F12°C & Cloudy

Wind is 7 mph11 km/h from the Southwest, gusting to 16 mph26 km/h
April 14
1pm53°F12°C8 mph12 km/h SouthwestMostly Cloudy
2pm52°F11°C9 mph15 km/h WestMostly Cloudy
3pm51°F11°C12 mph19 km/h WestMostly Cloudy
4pm50°F10°C17 mph27 km/h WestWindy
5pm50°F10°C18 mph28 km/h WestWindy
6pm50°F10°C18 mph28 km/h WestWindy
7pm51°F11°C17 mph28 km/h WestWindy
8pm52°F11°C16 mph26 km/h WestWindy
9pm54°F12°C16 mph25 km/h WestWindy
10pm55°F13°C14 mph23 km/h WestPartly Cloudy
11pm55°F13°C13 mph21 km/h WestPartly Cloudy
April 15
12am56°F13°C13 mph22 km/h WestMostly Cloudy
DateLowHighWindDayNight
April 1447°F8°C56°F13°C13 mph21 km/h from WestDrizzleClear
April 1546°F8°C65°F18°C11 mph18 km/h from SouthwestMostly ClearPartly Cloudy
April 1651°F10°C75°F24°C6 mph10 km/h from SouthwestMostly ClearPartly Cloudy
April 1756°F13°C73°F23°C6 mph10 km/h from SouthwestMostly CloudyMostly Clear
April 1857°F14°C77°F25°C5 mph8 km/h from SouthwestPartly CloudyMostly Cloudy
April 1955°F13°C67°F20°C5 mph8 km/h from SouthwestDrizzleDrizzle
April 2050°F10°C65°F18°C10 mph16 km/h from NorthPartly CloudyMostly Clear

Yes

Low of 46°F8°C, High of 64°F18°C
Wind: 11 mph18 km/h
Precipitation: None

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