September in Dublin averages highs of 17 °C (63 °F) and lows of 11 °C (52 °F), with about 10 rainy days and 12 h 35 min of daylight.
September weather in Dublin at a glance
average high to low each dot ≈ 3 rainy days
Is September a good time to visit Dublin?
Mixed weather: cool and some rain. September is usually shoulder season in Dublin: fewer crowds than peak months, with prices often a little lower.
Our rule: a month scores 2 points for comfortable average highs of 18–28 °C (1 point for 14–18 or 28–32 °C) and 2 points for 5 or fewer rainy days (1 point for 6–10). Average highs above 35 °C or below 8 °C make it a tough month whatever the rain. A rainy day here means 2 mm of rain or more. 4 points = great, 3 = good, 2 = mixed, 0–1 = tough.
Holidays and events in September 2026
No public holidays fall in September 2026 in Ireland, so opening hours should be normal.
Things to do in Dublin in September
September's weather suits a mix of outdoor sights and museums, so the open-air ones come first.
- St Stephen's Green and Grafton Street outdoors
- Howth cliff walk — 30 min by DART outdoors
- Trinity College and the Book of Kells — timed tickets indoors
- Guinness Storehouse indoors
- Kilmainham Gaol — book well ahead indoors
- Traditional music pubs indoors
Where to stay: Around Temple Bar and St Stephen's Green to walk everywhere; Smithfield or Portobello for better value.
What to pack for Dublin in September
- Layers and a light jacket: days around 17 °C (63 °F), nights near 11 °C (52 °F).
- An umbrella or a light waterproof: about 10 days this month see real rain.
- Comfortable walking shoes.
What a day in Dublin costs
| Budget traveller | Mid-range | |
|---|---|---|
| Typical total per person, per day | €70–160 | €200–400 |
Excluding flights. September is usually shoulder season in Dublin: fewer crowds than peak months, with prices often a little lower.
September in nearby cities
| City | High / low | Rainy days | Verdict |
|---|---|---|---|
| Edinburgh | 16° / 10° | 10 | Tough month |
| London | 20° / 11° | 8 | Good time to go |
| Amsterdam | 19° / 12° | 10 | Good time to go |
Want the whole trip planned? Join the Journey waitlist: tell it where, when and your budget, and it plans every day hour by hour.
FAQ
Is September a good time to visit Dublin?
By the numbers, September is a mixed month: cool and some rain, with average highs of 17 °C (63 °F) and about 10 rainy days. September is usually shoulder season in Dublin: fewer crowds than peak months, with prices often a little lower. The best months for weather are August.
How warm is Dublin in September?
Average highs are 17 °C (63 °F) and lows 11 °C (52 °F) (2015–2024 averages).
Does it rain a lot in Dublin in September?
Expect about 10 days with 2 mm of rain or more, about 83 mm in total. It is the 6th driest month of the year in Dublin.
Sources: climate averages from Open-Meteo historical weather (ERA5 reanalysis, 2015–2024); sea temperatures from the Open-Meteo marine API (2023–2024); public holidays from Nager.Date. Daylight is calculated for the 15th of the month. Averages are a guide, not a forecast. Costs are typical ranges per person per day, excluding flights.