The weather in Ireland in September is usually (but not always…) quite good.
Yes, the weather in Ireland is unpredictable, but we tend to have pretty OK Septembers, as you’ll see below.
The average temperature in Ireland in September see average highs of average highs of 13°C/55°F and average lows of 9°C/48°F.
Below, you’ll discover everything you know, from rainfall in September in Ireland to lots more.
Some quick need-to-knows about the weather in Ireland 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 Ireland in September:
1. The season
September, October and November are the fall months in Ireland. 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 Ireland. The weather in Ireland in September tends to be mild with a mix of dry and wet days (historical data below).
3. Average temperatures
The average temperature in Ireland in September sees average highs of average highs of 13°C/55°F and average lows of 9°C/48°F.
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 Ireland, but at a glance there are heaps of festivals in Ireland running in this month and there’s endless things to do in Ireland to choose from.
The average temperature in Ireland in September
The average temperature in Ireland in September is pretty good, as you can see from the graphic above, with avg. highs of average highs of 13°C/55°F and average lows of 9°C/48°F.
In Dublin, for example, the LTA (Long Term Average) temperature is 13.1°C/55.58°F.
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 Ireland in September weather data is via Met Eireann – the Irish Meteorological Service.
A comparison of September weather in Ireland in recent years
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 Ireland in September is fairly steady across the different years and in the various counties.
Rain in Ireland in September (measured in mm)
We get asked ‘Does in rain in Ireland in September?’ quite a bit. The answer is yes, yes it does (see our guide on what to wear in Ireland 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 Ireland, usually the west coast, get more rainfall than the east coast. This can be seen in the figures in the table above.
Weather in Dublin in September
The weather in Dublin in September tends to be fairly similar to the weather in many other parts of the country (flick back up to the tables above to compare).
For example, last year, in 2022, the average temperature in Dublin in September was 13.0°C/55.4°F
When we look at the rainy weather in Dublin in September last year, the capital recorded 127.9mm.
Learn more about visiting the capital during this month in our guide to Dublin in September.
FAQs about the weather in Ireland in September
We’ve had a lot of questions over the years asking about everything from ‘Does it rain in Ireland 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.
Is September rainy season in Ireland?
The LTA (Long Term Average) rainfall in Ireland in September is 59.5mm (Dublin). This is compared to 73.3mm in August, 79.0mm in October and 72.9mm in November.
What is the weather in Ireland in September like?
September weather in Ireland tends to be mild with highs of 13°C/55°F and lows of 9°C/48°F. Rain wise, the LTA (Long Term Average) rainfall in Dublin, for example, is 59.5mm.
What is the average temperature in Ireland in September?
Ireland experiences average highs of 13°C/55°F and average lows of 9°C/48°F. In Dublin, for example the LTA (Long Term Average) is 13.1°C/55.58°F for September.
Keith O’Hara has lived in Ireland for 34 years and has spent most of the last 10 years creating what is now The Irish Road Trip guide. Over the years, the website has published thousands of meticulously researched Ireland travel guides, welcoming 30 million+ visitors along the way. In 2022, the Irish Road Trip team published the world’s largest collection of Irish Road Trip itineraries. Keith lives in Dublin with his dog Toby and finds writing in the 3rd person minus craic altogether.