Bottrop's winters are cold and often quite chilly, with temperatures frequently dropping below freezing. Spring brings a gradual warming trend, with March and April seeing average highs around 20°C. Summer is mild but pleasant, with July being the warmest month, while August and September see slightly cooler temperatures. Autumn can be cool and unpredictable, with October experiencing temperature fluctuations from near-freezing to over 19°C on warmer days.