September Weather in Castlemartyr, Ireland

Last updated: March 17, 2025

Experience the charming September weather in Castlemartyr, Ireland, where temperatures delightfully fluctuate between a maximum of 22°C (72°F) and a minimum of 4°C (40°F). The average temperature hovers around a pleasant 14°C (57°F), making it an inviting time for outdoor exploration. However, expect some moisture, as the region receives approximately 77 mm (3.0 in) of precipitation over 13 days, complemented by a high humidity level of 85%. With its rich landscapes and refreshing climate, September offers a unique charm that beckons travelers to embrace its idyllic fall atmosphere.

September Temperature in Castlemartyr

As summer gracefully transitions into autumn, Castlemartyr, Ireland experiences a noticeable shift in temperatures during September. With minimums settling around 4°C (40°F), the days start chilling slightly, while the average temperature lingers at a comfortable 14°C (57°F). Daytime highs can still reach 22°C (72°F), allowing for pleasant afternoons that echo the warmth of summer. This month marks a significant change from the peaks of summer, reflecting a gradual cooling trend as the vibrant greens begin to morph into the rich hues of fall. Enjoying outdoor activities during September is certainly delightful, as the crisp air beckons both locals and visitors alike to embrace the beauty of this enchanting Irish village.

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

The chart illustrates September temperature patterns in Castlemartyr, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec444545485257616057524846
Data source: Temperature data for Castlemartyr generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Castlemartyr

September in Castlemartyr, Ireland, brings a moderate precipitation level of 77 mm (3.0 in) over the month, experienced over 13 rainy days. This is a slight decrease from the more abundant rainfall of August, which saw 103 mm (4.1 in), indicating a transition toward the drier fall months. Despite fewer rainy days than earlier months, the steady precipitation helps maintain lush greenery in the area as summer fades. This trend sets the stage for a wetter October ahead, which typically experiences higher rainfall, with average precipitation jumping to 121 mm (4.7 in). Overall, September serves as a bridging period, balancing the tail end of summer showers with the approaching autumn rains.

September Precipitation Trends in Castlemartyr

The chart displays monthly precipitation patterns in Castlemartyr, 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.
JanFebMarAprMayJunJulAugSepOctNovDec68124978075677010377121115129
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Castlemartyr

As September rolls in, Castlemartyr maintains a consistent humidity level of 85%, contributing to the lush, vibrant landscapes typical of this Irish gem. This slight uptick reflects the area's overall pattern, where humidity levels remain high throughout the year, peaking in October at 86%. Notably, the transition into autumn doesn't bring significant changes; humidity remains stable, hovering between 84% and 86% from April through November. While January and December see a dip to 83%, the rest of the months hold firmly in the 84% to 85% range, making for a delightful, albeit damp, climate that locals and visitors alike have come to embrace.

September Average Humidity in Castlemartyr

This chart illustrates the average monthly humidity levels in Castlemartyr, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec83%85%84%84%84%85%85%84%85%86%84%83%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Castlemartyr

In Castlemartyr, Ireland, the UV Index experiences a notable shift throughout the year, with September showcasing a UV Index of 5, placing it in the moderate exposure category. This marks a decrease from the peak summer months of June and July, which reached a high index of 8, resulting in a burn time of just 15 minutes. As the warm season transitions into autumn, residents and visitors can enjoy 30 minutes of safe sun exposure in September, similar to the preceding April and October. This trend reflects a gradual decline in UV levels as daylight shortens, but it's still wise to remain cautious during outdoor activities. For a deeper dive into the UV trends throughout the year, explore the full details at Castlemartyr UV Index.

Maximum UV Index Levels in Castlemartyr for September

The chart shows the monthly maximum UV Index (UVI) for Castlemartyr 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.
JanFebMarAprMayJunJulAugSepOctNovDec124578875421
Data source: Castlemartyr 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.

September Sunshine in Castlemartyr

September in Castlemartyr, Ireland, enjoys a delightful 298 hours of sunshine, making it one of the brighter months in the latter half of the year. As summer transitions into autumn, the sunshine begins to wane, yet September still holds strong with a generous share of daylight compared to the dreariness of the upcoming months. The sun-kissed days of July and August set high expectations, and while September's hours do drop, they still significantly outshine the winter months that follow, like November's meager 129 hours and December's 103 hours. This charming blend of warmth and light during September serves as a gentle farewell to summer, inviting residents and visitors alike to savor the last golden days before the chill of autumn takes hold.

Monthly Sunshine Duration in Castlemartyr: September Highlighted

The September sunshine duration represents the total number of hours Castlemartyr experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec89h140h197h307h392h385h396h353h298h235h129h103h
Data source: Castlemartyr September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Castlemartyr During September

In Castlemartyr, Ireland, the likelihood of sunny weather in September sees a decline, with only a 21% chance of sunshine. As summer fades, this month experiences a noticeable drop compared to the peaks of spring and early summer, where April enjoys a more promising 46% chance of sun. This trend suggests that while September may still carry remnants of the warmer months, the weather is increasingly transitioning toward the cooler, cloudier days of autumn. As we bid farewell to summer, residents and visitors alike should be prepared for the possibility of overcast skies, making those fleeting sunny moments all the more cherished.

Percentage of Sunny Days in September in Castlemartyr

The chart illustrates the percentage of sunny days in Castlemartyr throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Castlemartyr experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec32%23%23%46%31%26%29%27%21%20%30%21%
Data source: Castlemartyr September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Castlemartyr in September

As summer gives way to autumn, September in Castlemartyr, Ireland, sees a graceful decline in daylight, with an average of 12 hours illuminating the day. This marks a gentle transition from the height of summer's 16-hour days in June and July, showcasing nature's shift as the lush greenery starts to give way to autumn hues. Following the vibrant 14 hours of August, September signals a subtle cooling down, leading us toward the shorter days of October, where daylight shrinks to 10 hours. This gradual reduction not only influences the daily rhythms of life but also invites residents and visitors alike to savor the softer, golden light of early autumn—perfect for enjoying the serene landscapes that Ireland is renowned for.

Average Daylight Hours in Castlemartyr for September

The chart illustrates the variation in daylight duration in Castlemartyr throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 20m9h 56m11h 55m13h 56m15h 41m16h 37m16h 7m14h 32m12h 35m10h 35m8h 47m7h 49m
Data source: Castlemartyr daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Castlemartyr

In Castlemartyr, Ireland, the September winds gently whisper with an average speed of 3.7 m/s (8 mph), marking a subtle decline as summer bows to the onset of autumn. This shift follows the more spirited breezes of late summer, where August maintained an average of 4.0 m/s (9 mph). Notably, September's winds are among the calmest of the year, reflecting a broader trend of diminishing gusts as the seasons transition. The seasonal wind patterns show a gradual fluctuation, with January starting off brisk at 4.7 m/s (11 mph), while autumn months like October begin to pick up again, hinting at the inevitability of winter's approach. Overall, the September winds in Castlemartyr serve as a gentle reminder of nature's cyclical rhythm.

Average September Wind Speed in Castlemartyr

The chart displays monthly wind speed patterns in Castlemartyr, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec4.76.74.83.94.63.93.44.03.7 m/s4.94.45.5
Data source: Castlemartyr September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Castlemartyr Compares to Other Months

The weather in Castlemartyr changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Castlemartyr and find detailed weather information for every month.

September and January exhibit contrasting weather conditions. In September, temperatures range from a mild 4°C (40°F) to a warm 22°C (72°F), with an average of 14°C (57°F). The month experiences 77 mm (3.0 in) of precipitation over 13 days, coupled with high humidity at 85%. In stark contrast, January sees much colder temperatures, with a minimum of -3°C (27°F) and a maximum of only 13°C (56°F), averaging at 7°C (44°F). While it has slightly less precipitation at 68 mm (2.7 in) over 11 days, the humidity remains relatively high at 83%. For a detailed look at January weather, visit Castlemartyr weather in January.

September and February present distinct weather characteristics, reflecting the transition from late summer to winter. In September, temperatures range from a mild 4°C (40°F) at night to a pleasant maximum of 22°C (72°F) during the day, with an average of 14°C (57°F). Though there is notable precipitation of 77 mm (3.0 in) over 13 days, humidity remains relatively high at 85%. In contrast, February brings colder conditions, with minimum temperatures dipping to -1°C (31°F) and maximum temperatures only reaching 13°C (56°F), averaging at 7°C (45°F). This month experiences heavier rainfall, totaling 124 mm (4.9 in) over 17 days, while humidity remains consistent at 85%. For more details on February weather, you can visit Castlemartyr weather in February.

In September, temperatures generally range from a cool 4°C (40°F) at night to a pleasant 22°C (72°F) during the day, with an average temperature of 14°C (57°F). The month experiences some rainfall, accumulating about 77 mm (3.0 in) over approximately 13 days, and maintains a high humidity level of 85%. In contrast, March brings much colder temperatures, with nightly lows dipping to -5°C (24°F) and daytime highs peaking at 14°C (58°F), resulting in an average of only 7°C (45°F). Precipitation is slightly higher in March, totaling 97 mm (3.8 in) across around 16 days, with humidity levels remaining relatively similar at 84%. For more detailed information on weather patterns during this time, you can visit Castlemartyr weather in March.

In comparing the weather of September and April, we find notable differences in temperature and precipitation patterns. September generally boasts milder temperatures, with a minimum of 4°C (40°F) and a maximum of 22°C (72°F), averaging around 14°C (57°F). In contrast, April experiences cooler conditions, featuring a minimum of 0°C (32°F) and a maximum of 16°C (62°F), with an average temperature of just 9°C (48°F). While both months see considerable precipitation—77 mm (3.0 in) in September and slightly higher at 80 mm (3.2 in) in April—April typically has fewer rainy days, totaling 11 compared to September's 13. Humidity levels are fairly similar, with September at 85% and April slightly lower at 84%. For more details on the climate specifics during April, visit Castlemartyr weather in April.

In September, the weather is generally mild with temperatures ranging from a minimum of 4°C (40°F) to a maximum of 22°C (72°F), averaging around 14°C (57°F). Precipitation is relatively high, with 77 mm (3.0 in) falling over 13 days, and the humidity sits at a notable 85%. Conversely, May experiences slightly cooler temperatures, with a minimum of 2°C (36°F) and a maximum of 21°C (69°F), averaging 11°C (52°F). The month also sees a bit less precipitation at 75 mm (3.0 in) over 12 rainy days, accompanied by a humidity level of 84%. For more specific details about May weather, you can check Castlemartyr weather in May.

When comparing the weather in September and June, both months exhibit similar average temperatures around 14°C (57°F), but nuances in their extremes and precipitation patterns are noteworthy. September experiences slightly cooler minimums at 4°C (40°F) and maximums reaching 22°C (72°F), while June has minimums of 6°C (44°F) and maximums of 24°C (75°F), making it the warmer of the two months. Additionally, September sees more precipitation, totaling 77 mm (3.0 in) over 13 days, compared to June's 67 mm (2.6 in) over 11 days, although humidity levels remain consistent at 85% for both months. For a detailed look at June weather specifics, check out Castlemartyr weather in June.

When comparing the weather in September to that of July, notable differences emerge. September tends to have cooler temperatures, with minimums dropping to 4°C (40°F) and an average of 14°C (57°F), compared to July's milder minimums of 8°C (47°F) and average of 16°C (61°F). While both months experience similar humidity levels at 85%, September sees slightly higher precipitation, with 77 mm (3.0 in) over 13 days, versus July's 70 mm (2.8 in) over 12 days. For more detailed insights on July's weather, you can check Castlemartyr weather in July.

In comparing the weather between August and September, September generally sees cooler temperatures, with a minimum of 4°C (40°F) compared to August's 7°C (45°F). The average temperature in September is 14°C (57°F), slightly lower than August's average of 15°C (60°F), while both months have similar maximum temperatures. September experiences less rainfall, with 77 mm (3.0 in) over 13 days, compared to August's 103 mm (4.1 in) across 14 days. Humidity levels remain comparable, sitting at 85% for September and slightly lower at 84% for August. For more specific details about August's weather, you can visit Castlemartyr weather in August.

In September, the weather is characterized by milder temperatures, with a minimum of 4°C (40°F) and an average of 14°C (57°F), reaching a maximum of 22°C (72°F). It experiences 77 mm of precipitation over about 13 days, accompanied by high humidity levels at 85%. In contrast, October sees a slight drop in temperature, with a minimum of 2°C (36°F) and an average of 11°C (53°F), peaking at 17°C (63°F). Precipitation increases to 121 mm, occurring over 16 days, and humidity rises slightly to 86%. For more detailed information, you can visit Castlemartyr weather in October.

September typically showcases more moderate temperatures, with an average of 14°C (57°F) and maximums reaching up to 22°C (72°F). In contrast, November sees cooler conditions, with an average of just 9°C (48°F) and maximums peaking at 15°C (59°F). Additionally, November experiences more precipitation, totaling 115 mm (4.5 in) over 16 days, compared to September's 77 mm (3.0 in) across 13 days. Despite these differences, humidity levels remain relatively high in both months, with September at 85% and November slightly lower at 84%. For more detailed information, visit Castlemartyr weather in November.

September weather is generally milder with average temperatures ranging from 4°C (40°F) to a maximum of 22°C (72°F), making it a pleasant transition from summer. In contrast, December experiences colder temperatures, with averages between -1°C (31°F) and a maximum of 13°C (56°F), signaling the onset of winter. Additionally, September sees less precipitation, totaling 77 mm (3.0 in) over 13 days, while December is wetter, accumulating 129 mm (5.1 in) across 17 days. Humidity levels are similar in both months, reaching around 85% in September and slightly lower at 83% in December. For a closer look at the December climate, visit Castlemartyr weather in December.

Compare Castlemartyr's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Castlemartyr

As summer transitions to autumn, September in Castlemartyr showcases a unique blend of warm days and cooler nights, providing a gentle shift in the climate. With temperatures peaking at a comfortable 22°C, the month delivers a pleasant average that stands out in comparison to the chillier months that follow. However, this month also brings increased rainfall, recording around 77 mm over 13 days—making it one of the wetter periods of the year. Coupled with high humidity levels hovering around 85%, September embodies a mix of lingering warmth and the impending arrival of crisp fall air. For those curious about how this charming locale continues to evolve through the seasons, explore more on the Castlemartyr Climate page.