September weather forecast
Ireland

September signifies the arrival of autumn in Ireland, with average temperatures ranging from 12°C (53.6°F) to 17°C (62.6°F). This marks a noticeable decrease from the warmth of August, indicating the onset of cooler weather.

Compared to August, September experiences cooler and shorter days, as summer gives way to autumn. Daylight hours continue to decrease, with approximately 13 hours of daylight per day by the end of the month. Correspondingly, the duration of sunshine also decreases, with Dublin typically recording around 150 hours of sunshine throughout September.

Rainfall in September averages between 70mm (2.76") and 80mm (3.15"), mirroring the levels seen in August. The pattern of rainfall remains the same, with the west receiving more precipitation than the east. Wind conditions across the country are generally moderate, although the western coastal areas can experience windier days due to the Atlantic influence.

Sea temperatures around Ireland's coast begin to decrease in September, averaging between 14°C (57.2°F) and 15°C (59°F). Despite the falling temperatures, the coastal regions still enjoy a milder climate due to the moderating effect of the surrounding waters.

---

• Dublin - September »
  On the last day of September, sunrise is at 7:25 am and sunset at 7:03 pm IST. In Dublin the average seawater temperature in September is 14.8°C (58.6°F).
• Cork - September »
  September's advent in Cork presents an average high-temperature of a still comfortable 16°C (60.8°F), indicating a slight variation from the conditions of the previous month. September marks the onset of autumn in Cork, but summer's warmth lingers, making it a pleasant time to visit.
• Galway - September »
  On the first day of September in Galway, sunrise is at 6:46 am and sunset at 8:25 pm. In Galway, during September, the rain falls for 20 days and regularly aggregates up to 93mm (3.66") of precipitation.
• Limerick - September »
  The month with the least rainfall in Limerick is September, when the rain falls for 17.1 days and typically collects 39mm (1.54") of precipitation. In Limerick in September, it is raining for 17.1 days, with typically 39mm (1.54") of accumulated precipitation.
• Waterford - September »
  In Waterford in September, during 10.1 rainfall days, 83mm (3.27") of precipitation is typically accumulated. In Waterford, in September, during 10.1 rainfall days, 83mm (3.27") of precipitation is typically accumulated.
• Drogheda - September »
  The months with the highest humidity in Drogheda are July through September and December, with an average relative humidity of 87%. On the first day of September in Drogheda sunrise is at 6:35 am and sunset at 8:15 pm.
• Dundalk - September »
  September's arrival in Dundalk brings an average high-temperature of a mild 15.1°C (59.2°F), demonstrating subtle variation from the preceding month. September brings further reduction in Dundalk's average temperatures from 9°C (48.2°F) to 15.1°C (59.2°F), affirming the season's shift towards fall.
• Swords - September »
  Moving into September, autumn asserts its presence in Swords with cooler temperatures, shorter daylight hours, and increased humidity. In Swords in September, it is raining for 15 days, with typically 60mm (2.36") of accumulated precipitation.
• Bray - September »
  On the first day of September in Bray sunrise is at 6:35 am and sunset at 8:13 pm. September in Bray ushers in the start of fall, though the last fragments of summer are still palpable.
• Kilkenny - September »
  On the first day of September in Kilkenny sunrise is at 6:40 am and sunset at 8:16 pm. In Kilkenny in September, it is raining for 10 days, with typically 69mm (2.72") of accumulated precipitation.
• Ennis - September »
  On the first day of September in Ennis sunrise is at 6:47 am and sunset at 8:24 pm. As Ennis transitions into September, the average high-temperature stands at a still refreshing 15.8°C (60.4°F), offering little variation from the preceding month.