Stolberg's winters are typically cool and unpredictable, with temperatures often dipping below freezing but occasionally rising into the mid-teens. Spring brings mild conditions, with temperatures gradually warming up towards the end of April and May. Summer is generally warm, with highs in the mid-twenties and lows around 5-10°C, although July can be slightly cooler than August. Autumn is similar to spring, with a gradual cooling trend, while September is often still quite pleasant. Winters are generally the coolest time of year, with temperatures averaging just above or below freezing.