Winters in Saint-Etienne are cold and unpredictable, with temperatures fluctuating between freezing and mild. January is the coldest month, with average temperatures ranging from -10°C to 15°C, while February sees a slight warming trend. Spring arrives in March, with temperatures gradually increasing to an average of 7°C by the end of the month. Summers are warm and pleasant, with July and August often seeing highs above 30°C, but also experiencing cooler mornings. Autumn is marked by a return to chilly temperatures, with November and December averaging around 5-4°C respectively.