Weather: Lisbon — September

September is typically excellent for visiting Lisbon, with average highs of 23°C and around 4 rainy days. Plan your activities accordingly—outdoor sightseeing is best on dry days, while rainy days are perfect for museums and indoor attractions.

Evenings in Lisbon during September are mild at 18°C. A light cardigan or long sleeves for evenings is usually enough. Outdoor dining remains comfortable, making it a great time to enjoy rooftop bars and terrace restaurants.

With highs of 23°C and lows of 18°C in September, we recommend: Sunscreen SPF 30+, Sunglasses, Comfortable walking shoes. Layering is key as temperatures can vary between air-conditioned interiors and outdoors. Comfortable walking shoes are essential for cobblestone streets.

Lisbon typically sees around 4 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.

September is suitable for swimming in Lisbon, though the water may feel refreshing at first. Air temperatures average 23°C, and most swimmers find it enjoyable once they're in. Midday is usually the warmest time for a dip.

In September, Lisbon gets approximately 12.5 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 Lisbon. 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.