Yes

you do need a jacket based on the weather in Girraween NSW 2145, Australia 1 second ago

Why? Because it's cool. Pleasantly cool, but cool.
54°F12°C & Clear

Wind is 5 mph8 km/h from the NW, gusting to 11 mph18 km/h
September 20
11am53°F12°C5 mph9 km/h NWClear
12pm52°F11°C6 mph9 km/h NWClear
1pm51°F11°C6 mph10 km/h NWMostly Clear
2pm51°F11°C6 mph10 km/h NClear
3pm50°F10°C6 mph9 km/h NClear
4pm49°F10°C5 mph8 km/h NClear
5pm52°F11°C3 mph6 km/h NClear
6pm56°F14°C4 mph6 km/h NWClear
7pm62°F16°C5 mph8 km/h NWClear
8pm65°F18°C5 mph9 km/h NWClear
9pm69°F20°C5 mph9 km/h WClear
10pm71°F22°C6 mph9 km/h WClear
DateLowHighWindDayNight
September 2049°F10°C74°F23°C7 mph11 km/h from WClearClear
September 2148°F9°C76°F25°C7 mph11 km/h from WMostly ClearClear
September 2248°F9°C81°F27°C5 mph7 km/h from WClearMostly Cloudy
September 2353°F11°C79°F26°C6 mph9 km/h from NEMostly CloudyMostly Cloudy
September 2459°F15°C82°F28°C11 mph18 km/h from NWCloudyRain
September 2549°F10°C62°F17°C8 mph14 km/h from SRainMostly Cloudy
September 2647°F9°C66°F19°C6 mph10 km/h from EMostly CloudyMostly Cloudy

Yes

Low of 47°F9°C, High of 76°F25°C
Wind: 7 mph11 km/h
Precipitation: None

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