Yes

you do need a jacket based on the weather in Flagstaff, AZ 86002, USA 5 seconds ago

Why? Because it's cold enough that makes you wish you had a hat, but you're still too proud to admit it!
37°F3°C & Clear

Wind is 9 mph15 km/h from the East, gusting to 17 mph28 km/h
October 28
1pm37°F3°C10 mph16 km/h EastClear
2pm37°F3°C10 mph17 km/h EastClear
3pm42°F6°C12 mph19 km/h EastClear
4pm46°F8°C14 mph22 km/h EastClear
5pm50°F10°C14 mph23 km/h EastClear
6pm53°F12°C14 mph23 km/h EastClear
7pm56°F13°C14 mph23 km/h EastClear
8pm59°F15°C12 mph19 km/h EastClear
9pm60°F16°C12 mph19 km/h EastClear
10pm60°F15°C12 mph19 km/h EastClear
11pm58°F15°C11 mph18 km/h NortheastClear
October 29
12am55°F13°C10 mph16 km/h NortheastClear
DateLowHighWindDayNight
October 2835°F2°C60°F16°C12 mph19 km/h from EastClearClear
October 2938°F3°C65°F18°C5 mph8 km/h from EastClearClear
October 3041°F5°C69°F20°C4 mph6 km/h from SouthwestClearMostly Clear
October 3142°F6°C66°F19°C8 mph13 km/h from WestMostly ClearClear
November 139°F4°C69°F20°C3 mph5 km/h from NorthClearClear
November 244°F6°C73°F23°C4 mph6 km/h from SouthClearMostly Clear
November 345°F7°C67°F19°C5 mph8 km/h from SouthwestPartly CloudyMostly Clear

Yes

Low of 37°F3°C, High of 65°F19°C
Wind: 5 mph8 km/h
Precipitation: None

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