Winters in West Allis are frigid, with temperatures often dropping below freezing and averaging around -4°C in January. The coldest months, January and February, see temperatures range from as low as -26°C to a relatively mild 10°C. Spring brings gradual warming, with March temperatures ranging from -12°C to 18°C, but April is still quite cool, with highs only reaching up to 26°C on average. Summer is warm, with July and August averaging around 22-23°C, while September sees a slight cooling trend back towards autumnal temperatures. Autumn is mild, with October temperatures ranging from -1°C to 30°C before the cold winter months return in November and December.