Weather in Dublin in September (Need-to-Knows)

The weather in Dublin in September is usually (but not always…) quite good.

Yes, the weather in Dublin is unpredictable, but we tend to have pretty OK Septembers, as you’ll see below.

And, to top it off, the LTA (Long Term Average) temperature in Dublin in September 13.1°C/55.58°F with rainfall measuring 59.5mm.

Below, you’ll discover everything you know, from rainfall in September in Dublin to lots more.

Some quick need-to-knows about the weather in Dublin in September

OK, let’s get you up-to-speed nice and quickly. The points below will give you a quick insight into the weather in Dublin in September:

1. The season

September, October and November are the fall months in Dublin. The kids are back to school and, from a tourist perspective, this is known as the ‘Shoulder Season’ (i.e. the season between peak and the off-season).

2. The weather in general

September is, in my opinion, one of the best months to visit Dublin. The weather in Dublin in September tends to be mild with a mix of dry and wet days (historical data below).

3. Average temperatures

The LTA (Long Term Average) temperature in Dublin in September is 13.1°C/55.58°F with rainfall measuring 59.5mm.

4. Long days

At the start of September, the sun rises at 05:41 and it sets at 21:20. This makes planning your Ireland itinerary easy as you’ve lots of time to work with.

5. Lots to do

We go into the various things to see and do in our guide to September in Dublin, but at a glance there are heaps of festivals in Ireland running in this month and there’s endless things to do in Dublin to choose from.

The average temperature in Dublin in September

The LTA (Long Term Average) temperature in Dublin in September 13.1°C/55.58°F with rainfall measuring 59.5mm.

Now, this can vary quite a bit year to year, so I’ll pop in a chart comparing recent years from different weather stations.

Please note that all of the Dublin in September weather data is via Met Eireann – the Irish Meteorological Service.

A comparison of September weather in Dublin in recent years

County	2022	2021	2020
Dublin	13.0°C/55.4°F	14.7°C/58.46°F	12.8°C/55.04°F
Galway	13.1°C/55.58°F	14.8°C/58.64°F	13.0°C/55.4°F
Cork	14.9°C/58.82°F	15.4°C/59.72°F	14.2°C/57.56°F
Kerry	14.4°C/57.92°F	15.4°C/59.72°F	14.1°C/57.38°F

The table above will give you a sense of the average temperature in Dublin in September along with Galway, Cork and Kerry over the last number of years.

As you can see, the average temperature in Dublin in September is fairly steady across the different years and in the various counties.

Rain in Dublin in September (measured in mm)

County	2022	2021	2020
Dublin	127.9	42.0	60.9
Galway	114.2	91.1	90.3
Cork	133.7	83.2	48.4
Kerry	175.8	121.8	94.5

We get asked ‘Does in rain in Dublin in September?’ quite a bit. The answer is yes, yes it does (see our guide on what to wear in Dublin in September).

However, it rains considerably less during September than it does in the other months of the year.

Now, it’s also worth noting that certain parts of Dublin, usually the west coast, get more rainfall than the east coast. This can be seen in the figures in the table above.

FAQs about the weather in Dublin in September

We’ve had a lot of questions over the years asking about everything from ‘Does it rain in Dublin in September?’ to ‘What’s on?’.

In the section below, we’ve popped in the most FAQs that we’ve received. If you have a question that we haven’t tackled, ask away in the comments section below.