Eskilstuna's winters are cold and dark, with temperatures often below freezing, averaging around -4°C in February. Spring is a slow warming period, with March being the first month to see average temperatures rise above 0°C. Summer brings mild warmth, with July being the warmest month, averaging 20°C. Autumn is a gradual cooling, with September and October experiencing some warmer days. The coldest months are usually December, January, and February, while the warmest months are June, July, and August.