Yes

you do need a jacket based on the weather in General William J. Fox Airfield, 4555 W Avenue G # 1, Lancaster, CA 93536, USA 1 second ago

Why? Because it's pretty chilly.
55°F13°C & Clear

Wind is 9 mph14 km/h from the SW, gusting to 14 mph22 km/h
April 19
11am60°F16°C10 mph15 km/h SWClear
12pm65°F19°C11 mph17 km/h SWClear
1pm70°F21°C11 mph18 km/h WClear
2pm74°F23°C12 mph19 km/h WMostly Clear
3pm76°F25°C13 mph21 km/h WPartly Cloudy
4pm78°F25°C15 mph24 km/h WPartly Cloudy
5pm79°F26°C16 mph26 km/h WWindy
6pm80°F27°C17 mph28 km/h WWindy
7pm79°F26°C17 mph28 km/h WWindy
8pm77°F25°C16 mph26 km/h WWindy
9pm75°F24°C15 mph24 km/h WWindy
10pm71°F22°C13 mph21 km/h WClear
DateLowHighWindDayNight
April 1953°F12°C80°F27°C14 mph22 km/h from WMostly ClearClear
April 2054°F12°C86°F30°C9 mph14 km/h from WClearClear
April 2156°F13°C89°F31°C6 mph9 km/h from SWClearClear
April 2255°F13°C83°F28°C13 mph21 km/h from SWClearClear
April 2352°F11°C73°F23°C17 mph28 km/h from SWWindyMostly Clear
April 2448°F9°C69°F20°C16 mph26 km/h from SWWindyMostly Clear
April 2547°F8°C64°F18°C17 mph27 km/h from SWWindyMostly Clear

Yes

Low of 55°F13°C, High of 86°F30°C
Wind: 9 mph14 km/h
Precipitation: None

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