Vlaardingen's winters are cool and unpredictable, with temperatures fluctuating between freezing and mild days, averaging around 6°C in January. As spring approaches, temperatures gradually rise, with March marking a notable increase to an average of 7°C. Summer months bring warm but not scorching temperatures, peaking at an average high of 17°C in July and August. Autumn is characterized by a gentle decline in temperature, with September being the mildest month before dropping to around 11°C in November. The coldest period returns in December, with temperatures averaging around 8°C.