What September feels like in Dublin
In Dublin, September brings early autumn. Afternoons are cool, pleasant for walking as long as you keep a layer on. There is little difference between day and night: nights are cool, and evenings feel much like the afternoon. Moisture in the air gives the cold a damp edge.
Rain in Dublin in September
Showers are a regular feature, arriving about one day in 3. Wet days average about 6.6 mm (0.3 in), enough to soak you without an umbrella. The yearly figure is similar, around 5.8 mm per wet day.
Daylight and sunshine in September
On 15 September the sun rises at about 6:57 am and sets around 7:44 pm local time, giving 12 h 47 min of daylight. Days are getting shorter: 2 h 5 min less daylight than in mid-August. The sun is out for roughly 64% of those daylight hours, so there are plenty of bright spells.
How September compares to the rest of the year
Ranked by average high, September comes out as the 4th warmest month in Dublin. Compared with August, afternoons are 1.9°C (3.4°F) cooler, with 5 mm less rain. Temperatures keep falling into October. The next month's average high: 14°C (57.2°F).
Who September suits
- Sightseeing: a good fit — the weather rarely gets in the way of a city walk.
- Parks & outdoor: a good fit — comfortable for long walks and picnics.
- Beach: less ideal — the sea air is too cool.
Tips for visiting Dublin in September
Rain Protection
A packable rain jacket saves the day on showery afternoons.
Light Jacket
A light jacket or knit layer is enough for most of the day.
Sunglasses
Plenty of sun, so bring sunglasses and a cap.
Quick questions
How warm is Dublin in September?
Expect around 16.8°C (62.2°F) in the afternoon and 11.3°C (52.3°F) at night, which most visitors would call cool.
Does it rain a lot in Dublin in September?
Quite a lot — 79 mm spread over about 12 days.
What should I wear in Dublin in September?
Based on the averages: rain protection, a light jacket and sunglasses. Evenings feel similar to the day, so the same clothes work from morning to night.
Is September or October better for visiting Dublin?
On our 12-month climate ranking, September comes out ahead (#4 of 12 vs #6). October is cooler and has more rainy days.