Weather: Luxembourg City — September

September is typically excellent for visiting Luxembourg City, with average highs of 20°C and around 11 rainy days. Plan your activities accordingly—outdoor sightseeing is best on dry days, while rainy days are perfect for museums and indoor attractions.

Nights in Luxembourg City during September are cool at around 11°C. Bring a jacket or sweater for evenings, especially if you plan to dine outdoors or take evening walks. The temperature drop from day to night can be noticeable.

With highs of 20°C and lows of 11°C in September, we recommend: Warm layer for evenings, Compact umbrella, Waterproof jacket/shell, Comfortable walking shoes. Layering is key as temperatures can vary between air-conditioned interiors and outdoors. Comfortable walking shoes are essential for cobblestone streets.

Luxembourg City typically sees around 11 rainy days in September. Rain is usually in the form of brief showers rather than all-day downpours, so a compact umbrella is sufficient. Mornings tend to be drier, making them ideal for outdoor sightseeing.

In September, Luxembourg City gets approximately 12.7 hours of daylight per day. This affects how much sightseeing you can fit in—longer days mean more time for outdoor activities, while shorter days are perfect for cozy museum visits and early dinners.

Yes, September is peak season in Luxembourg City. Expect higher prices for accommodation and more crowds at popular attractions, but also the best weather conditions. Book hotels and major attractions in advance to secure availability and better rates.