Yes

you do need a jacket based on the weather in Arvada, CO, USA 1 second ago

Why? Because it's cold. simple as that.
37°F3°C & Partly Cloudy

Wind is 4 mph7 km/h from the NW, gusting to 8 mph13 km/h
March 29
9am37°F3°C4 mph7 km/h NWPartly Cloudy
10am39°F4°C3 mph5 km/h WPartly Cloudy
11am43°F6°C3 mph5 km/h SMostly Clear
12pm46°F8°C4 mph7 km/h EMostly Clear
1pm48°F9°C6 mph10 km/h NEMostly Cloudy
2pm51°F10°C7 mph11 km/h NEMostly Cloudy
3pm52°F11°C6 mph10 km/h NEMostly Cloudy
4pm54°F12°C6 mph10 km/h NEMostly Cloudy
5pm55°F13°C5 mph7 km/h NEMostly Cloudy
6pm54°F12°C5 mph7 km/h NEMostly Cloudy
7pm52°F11°C8 mph13 km/h NMostly Cloudy
8pm49°F9°C8 mph13 km/h NMostly Cloudy
DateLowHighWindDayNight
March 2937°F3°C55°F13°C6 mph9 km/h from NEMostly CloudyMostly Cloudy
March 3035°F2°C60°F16°C4 mph7 km/h from NPartly CloudyClear
March 3137°F3°C64°F18°C7 mph12 km/h from SWMostly ClearMostly Cloudy
April 136°F2°C52°F11°C7 mph11 km/h from NEMostly CloudyPartly Cloudy
April 231°F-1°C59°F15°C6 mph9 km/h from NClearClear
April 336°F2°C67°F19°C3 mph5 km/h from SClearClear
April 439°F4°C68°F20°C5 mph8 km/h from SMostly ClearPartly Cloudy

Yes

Low of 35°F2°C, High of 60°F16°C
Wind: 4 mph7 km/h
Precipitation: None

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