Winters in Katwijk are mild, with temperatures ranging from 1-10°C on average around 6°C. The months of January and February are the coolest, with occasional dips below freezing point. As spring approaches, temperatures gradually rise, reaching an average of 7°C by March and April. Summer brings warmer temperatures, peaking in June and July with averages around 14-16°C. Autumn is also mild, with a gentle decline in temperature from September to November before cooling down again in December.