Yes

you do need a jacket based on the weather in West Allis, WI, USA 1 second ago

Why? Because time to get cozy, it's freezing out there!

29°F-2°C & Cloudy

Wind is 11 mph18 km/h from the Southeast, gusting to 18 mph29 km/h

Date	Low	High	Wind	Day	Night
February 5	16°F-9°C	30°F-1°C	9 mph14 km/h from East	Cloudy	Snow
February 6	21°F-6°C	38°F3°C	17 mph27 km/h from West	Windy	Windy
February 7	14°F-10°C	27°F-3°C	8 mph12 km/h from West	Mostly Cloudy	Cloudy
February 8	22°F-6°C	30°F-1°C	10 mph16 km/h from East	Snow	Snow
February 9	15°F-10°C	24°F-4°C	6 mph10 km/h from Northwest	Mostly Cloudy	Partly Cloudy
February 10	10°F-12°C	27°F-3°C	6 mph9 km/h from West	Mostly Clear	Partly Cloudy
February 11	10°F-12°C	19°F-7°C	9 mph14 km/h from North	Mostly Cloudy	Mostly Cloudy

Low of 21°F-6°C, High of 38°F4°C
Wind: 17 mph27 km/h
Precipitation: None