Yes

you do need a jacket based on the weather in Gardiner, MT 59030, USA 1 second ago

Why? Because it's colder than a polar bear's pyjamas
28°F-2°C & Mostly Clear

Wind is 4 mph7 km/h from the N, gusting to 9 mph14 km/h
April 19
11pm27°F-3°C4 mph7 km/h NClear
April 20
12am25°F-4°C3 mph5 km/h NClear
1am24°F-4°C3 mph4 km/h NMostly Clear
2am23°F-5°C3 mph4 km/h NEMostly Clear
3am22°F-6°C2 mph4 km/h NEMostly Clear
4am21°F-6°C2 mph4 km/h NEPartly Cloudy
5am20°F-7°C2 mph4 km/h NEPartly Cloudy
6am19°F-7°C2 mph4 km/h NEPartly Cloudy
7am19°F-7°C2 mph4 km/h EPartly Cloudy
8am18°F-8°C2 mph3 km/h EPartly Cloudy
9am19°F-7°C2 mph3 km/h EPartly Cloudy
10am22°F-6°C2 mph3 km/h EMostly Clear
DateLowHighWindDayNight
April 1915°F-9°C36°F2°C6 mph9 km/h from NPartly CloudyMostly Clear
April 2018°F-8°C46°F8°C3 mph4 km/h from NWMostly ClearClear
April 2127°F-3°C53°F11°C9 mph14 km/h from SWMostly CloudyPartly Cloudy
April 2226°F-3°C48°F9°C7 mph11 km/h from WMostly ClearMostly Clear
April 2325°F-4°C53°F12°C4 mph7 km/h from SWMostly CloudyPartly Cloudy
April 2431°F-1°C57°F14°C5 mph8 km/h from SPartly CloudyMostly Cloudy
April 2534°F1°C48°F9°C6 mph9 km/h from SWRainMostly Cloudy

Yes

Low of 19°F-8°C, High of 46°F8°C
Wind: 3 mph4 km/h
Precipitation: None

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