Yes

you do need a jacket based on the weather in Gillette, WY, USA 1 second ago

Why? Because it's bitterly cold.
32°F0°C & Partly Cloudy

Wind is 9 mph14 km/h from the S, gusting to 14 mph23 km/h
March 28
9am32°F-0°C9 mph15 km/h SPartly Cloudy
10am35°F2°C9 mph15 km/h SMostly Clear
11am41°F5°C10 mph17 km/h SPartly Cloudy
12pm46°F8°C12 mph20 km/h SWPartly Cloudy
1pm50°F10°C14 mph22 km/h SWPartly Cloudy
2pm53°F12°C16 mph26 km/h SWWindy
3pm56°F13°C19 mph31 km/h SWWindy
4pm57°F14°C21 mph34 km/h SWWindy
5pm58°F14°C22 mph35 km/h SWWindy
6pm57°F14°C21 mph33 km/h SWWindy
7pm57°F14°C20 mph33 km/h SWWindy
8pm55°F13°C19 mph30 km/h SWWindy
DateLowHighWindDayNight
March 2830°F-1°C58°F14°C16 mph26 km/h from SWWindyMostly Cloudy
March 2930°F-1°C48°F9°C10 mph16 km/h from NWPartly CloudyMostly Cloudy
March 3030°F-1°C45°F7°C11 mph18 km/h from SEDrizzleCloudy
March 3128°F-2°C39°F4°C9 mph15 km/h from NEDrizzleSnow
April 127°F-3°C44°F6°C12 mph19 km/h from NWMostly CloudyMostly Clear
April 231°F-0°C56°F14°C11 mph18 km/h from NWMostly ClearClear
April 340°F4°C66°F19°C14 mph22 km/h from WMostly ClearMostly Cloudy

Yes

Low of 30°F-1°C, High of 48°F9°C
Wind: 10 mph16 km/h
Precipitation: None

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