Weather: Dublin — September

September is typically excellent for visiting Dublin, with average highs of 17°C and around 14 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 Dublin during September are mild at 12°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 17°C and lows of 12°C in September, we recommend: Layerable clothing, Light jacket, Compact umbrella, Waterproof jacket/shell. Layering is key as temperatures can vary between air-conditioned interiors and outdoors. Comfortable walking shoes are essential for cobblestone streets.

Dublin typically sees around 14 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, Dublin gets approximately 12.8 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 Dublin. 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.