September Weather in Castlefin, Ireland

Last updated: August 23, 2025

In Castlefin, Ireland, the average temperature in September hovers around 12°C (55°F). Expect a minimum of 1°C (34°F) and a comfortable maximum of 24°C (75°F). With an average humidity of 87%, it's important to stay hydrated. Be prepared for some rain, as 86 mm (3.4 in) of precipitation is likely over 17 days this month.

September Temperature in Castlefin

In September in Castlefin, the average temperature is 12°C (55°F). The maximum can reach 24°C (75°F), and the minimum can be as low as 1°C (34°F). This range makes Castlefin an ideal destination for travelers seeking mild weather and the opportunity to experience both warm days and cool evenings.

September Weather in Castlefin: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Castlefin, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Castlefin, September typically has an average temperature of 12°C (55°F), with highs reaching up to 24°C (75°F) and lows dropping to around 1°C (34°F).

Data source: Temperature data for Castlefin generated using information from the Copernicus Climate Change Service.

September Precipitation in Castlefin

In Castlefin in September, the precipitation amount is 86 mm (3.4 in) distributed over 17 days.

September Precipitation Trends in Castlefin

The chart displays monthly precipitation patterns in Castlefin, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Castlefin, September typically receives around 86 mm (3.4 inches) of precipitation spread over approximately 17 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

September Humidity in Castlefin

In Castlefin in September humidity is 87%. With an average temperature of 12°C (55°F), this humidity feels like a damp chill that clings to your skin, making outdoor activities less enjoyable and requiring extra layers for comfort while traveling.

September Average Humidity in Castlefin

This chart illustrates the average monthly humidity levels in Castlefin, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Castlefin is approximately 87%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Castlefin

In Castlefin in September, the maximum UV index reaches 5, which corresponds to a moderate Exposure Category. Under these conditions, the estimated time to burn is approximately 30 minutes. For more details, you can check the Hourly UV Index in Castlefin.

Maximum UV Index Levels in Castlefin for September

The chart shows the monthly maximum UV Index (UVI) for Castlefin in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Castlefin typically reaches 5, which falls under the moderate exposure category.

Data source: Castlefin September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How September Weather in Castlefin Compares to Other Months

Weather in Castlefin varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Castlefin, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Castlefin, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	5°C (41°F)	72 mm (2.8 inches)	84%	low
February Weather	5°C (42°F)	115 mm (4.5 inches)	84%	low
March Weather	6°C (43°F)	100 mm (3.9 inches)	83%	moderate
April Weather	8°C (47°F)	60 mm (2.4 inches)	84%	moderate
May Weather	11°C (52°F)	80 mm (3.2 inches)	83%	high
June Weather	13°C (56°F)	101 mm (4.0 inches)	83%	very high
July Weather	15°C (59°F)	95 mm (3.7 inches)	86%	very high
August Weather	14°C (58°F)	138 mm (5.4 inches)	86%	high
September Weather	12°C (55°F)	86 mm (3.4 inches)	87%	moderate
October Weather	10°C (50°F)	104 mm (4.1 inches)	87%	moderate
November Weather	7°C (45°F)	94 mm (3.7 inches)	88%	low
December Weather	6°C (43°F)	102 mm (4.0 inches)	84%	low