Yes

you do need a jacket based on the weather in Coolbellup WA 6163, Australia 1 second ago

Why? Because it's not very warm out and the wind is harsh and biting!
58°F14°C & Mostly Cloudy

Wind is 11 mph18 km/h from the Northwest, gusting to 20 mph32 km/h
September 13
2pm58°F14°C12 mph20 km/h NorthwestMostly Cloudy
3pm57°F14°C13 mph22 km/h NorthwestPartly Cloudy
4pm58°F14°C13 mph21 km/h NorthwestMostly Clear
5pm58°F14°C15 mph24 km/h NorthwestWindy
6pm58°F14°C16 mph26 km/h NorthwestWindy
7pm59°F15°C18 mph29 km/h NorthwestWindy
8pm60°F16°C21 mph34 km/h NorthwestWindy
9pm61°F16°C23 mph37 km/h NorthwestDrizzle
10pm62°F16°C24 mph39 km/h NorthwestRain
11pm62°F17°C24 mph38 km/h WestDrizzle
September 14
12am61°F16°C26 mph41 km/h WestDrizzle
1am62°F17°C23 mph37 km/h WestWindy
DateLowHighWindDayNight
September 1352°F11°C62°F17°C23 mph37 km/h from WestRainDrizzle
September 1449°F10°C61°F16°C14 mph23 km/h from SouthwestPartly CloudyMostly Cloudy
September 1548°F9°C62°F17°C8 mph12 km/h from NorthwestPartly CloudyMostly Cloudy
September 1652°F11°C65°F18°C16 mph25 km/h from WestRainPartly Cloudy
September 1751°F10°C63°F17°C10 mph16 km/h from SouthwestPartly CloudyMostly Cloudy
September 1851°F10°C66°F19°C7 mph12 km/h from SouthPartly CloudyClear
September 1950°F10°C70°F21°C6 mph10 km/h from SouthClearClear

Yes

Low of 49°F10°C, High of 61°F16°C
Wind: 14 mph23 km/h
Precipitation: 18% rain

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