Last updated: March 17, 2025
Dundalk experiences a temperate September, with maximum temperatures reaching a pleasant 22°C (72°F) and an average of 13°C (56°F). This transitional month sees minimum temps dipping to 3°C (37°F), urging locals to prepare for cooler days. Rainfall measures at approximately 74 mm (2.9 in) across 13 days, contributing to the region's lush greenery. With humidity soaring at 86%, visitors can expect a mix of sunny spells and occasional showers in this vibrant Irish town.
As September rolls into Dundalk, Ireland, the temperatures signal a gradual transition from the warm summer months to the cooler embrace of autumn. The minimum temperature settles around 3°C (37°F), while the average grants a comfortable 13°C (56°F), making it ideal for outdoor activities. As days continue to shorten, the maximum temperature still reaches a pleasant 22°C (72°F), reflecting the last vestiges of summer warmth. This month offers a delightful mix, presenting a slight chill in the mornings and evenings, but still plenty of opportunities for sunshine, reminding us that the beauty of fall is just around the corner.
In Dundalk, Ireland, September brings a notable shift in precipitation patterns, with 74 mm (2.9 in) of rainfall recorded over 13 days. This marks a decrease from the soaking summer months, particularly August, which saw a substantial 114 mm (4.5 in) over 18 days. As autumn sets in, rainfall begins to moderate, hinting at a transition towards the wetter conditions of October and November. The precipitation levels in September reflect a familiar trend in Dundalk's climate, where the balance between drier and wet seasons shapes the rich and vibrant greenery of the region. This month serves as a reminder of the ever-changing Irish weather, where early autumn can still bring a mix of sunshine and drizzling skies.
In September, Dundalk experiences a humidity level of 86%, which aligns with the generally elevated moisture levels seen throughout the summer months. Notably, this peak in humidity comes right after a consistent 85% during August, indicating that the late summer's warmth lingers into early autumn. As the year progresses, humidity gradually increases again, reaching its highest point of 87% in October. This trend highlights the persistent dampness characteristic of Dundalk’s climate, creating an environment that remains consistently humid from the spring through the fall. Overall, the humid conditions contribute to the region’s lush landscapes, making September an integral part of this captivating climate narrative.
In September, Dundalk experiences a moderate UV Index of 5, marking a transition as summer wanes into autumn. This means that while the sun's rays remain strong, the risk of harm from unprotected sun exposure is reduced compared to the peak months of June and July, which boasted a very high UV Index of 8. With a burn time of 30 minutes, it’s still wise for residents and visitors to stay mindful of sun safety, particularly during midday hours. As autumn approaches, the UV Index gradually declines from its summer highs, reflecting a seasonal shift that encourages outdoor enthusiasts to enjoy the milder weather while remaining protected. For more detailed information, check out the Dundalk UV Index.
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September in Dundalk, Ireland, offers a remarkable transition as the summer warmth lingers, contributing to a generous 283 hours of sunshine. This month clearly marks a shift from the peak of summer, as it follows a vibrant August, which recorded 325 hours of sunlight, yet it still outshines the drab days of autumn ahead. Comparatively, September maintains a healthy glow, far surpassing the more subdued months like November and December, which often struggle under cloudy skies. As the year progresses, the gradual decrease in hours can be seen, yet September shines brightly as it bids farewell to summer—a delightful reminder of the sun's lingering warmth before the days grow shorter.
As September rolls into Dundalk, Ireland, the likelihood of sunny weather becomes quite slim, with only a 19% chance of sunshine. This marks a continuation of the gentle decline in sunny days that begins in late summer, following the slightly more promising months of April (39%) and May (33%). Interestingly, September's prospects mirror those of July and August, both of which linger around 20%. The trend indicates that as the year progresses into autumn, the opportunity for clear skies diminishes, leaving residents and visitors alike to savor the fleeting warmth of summer while it lasts.
As summer gently fades into autumn, September in Dundalk, Ireland offers a delightful balance of daylight, with approximately 12 hours illuminating the day. This marks a gradual decrease from the sun-drenched peaks of June and July, where daylight stretched to an impressive 17 hours. The transition from the vibrant long days of summer to the shorter hours of fall is evident as September bridges the gap, providing a remarkable contrast to the 8 hours of daylight typical in January and November. While daylight decreases in the subsequent months, September remains a golden time for enjoying the lingering warmth and beauty of the season before winter settles in.
In Dundalk, Ireland, the September winds, averaging 3.3 m/s (7 mph), reflect a subtle transition from the summer's calmer breezes to the invigorating gusts of autumn. Throughout the year, the wind speeds display distinct fluctuations, with the spring months often experiencing a gentle flow, particularly in April, where it dips to 3.2 m/s (7 mph). As summer wanes, the winds begin to pick up, particularly noticeable in October when they rise to 4.3 m/s (10 mph). This pattern suggests that while September maintains a relatively moderate wind speed, the inhabitants may soon greet a brisker pace, as winter approaches and average speeds stabilize around 4.4 m/s (10 mph) in November and December. Such trends not only enhance the charm of Dundalk's autumnal landscape but also remind us of the inevitable shift in season that the winds herald.
The weather in Dundalk 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 Dundalk and find detailed weather information for every month.
September and January present a stark contrast in weather conditions. September boasts milder temperatures with a minimum of 3°C (37°F) and an average of 13°C (56°F), peaking at 22°C (72°F). The month sees considerable precipitation of 74 mm (2.9 in) spread over 13 days, accompanied by high humidity levels of 86%. In contrast, January is much colder, featuring a minimum temperature of -5°C (23°F) and an average of 5°C (42°F), with a maximum of 14°C (57°F). While January experiences less rainfall at 54 mm (2.1 in) over 10 days, the humidity remains fairly consistent at 85%. For a detailed look at January weather, you can check out Dundalk weather in January.
September and February exhibit notable contrasts in weather patterns. In September, temperatures range from a mild 3°C (37°F) at night to a comfortable 22°C (72°F) during the day, averaging around 13°C (56°F). The month experiences approximately 74 mm (2.9 in) of precipitation over about 13 days, with high humidity at 86%. In comparison, February presents a chillier atmosphere, with minimum temperatures dipping to -4°C (25°F) and a maximum of 14°C (58°F), averaging 6°C (43°F). The precipitation increases slightly to 85 mm (3.4 in) over about 15 days, while humidity remains the same at 86%. For more detailed insights, you might be interested in Dundalk weather in February.
September and March present contrasting weather patterns, despite both months exhibiting high humidity levels of 86%. In September, temperatures range from a minimum of 3°C (37°F) to a maximum of 22°C (72°F), with an average of 13°C (56°F), making it generally warmer than March. However, March experiences colder temperatures, with a minimum of -4°C (25°F) and a maximum of 16°C (61°F), leading to an overall average of 7°C (44°F). Additionally, while September sees 74 mm (2.9 in) of precipitation over 13 days, March has slightly higher precipitation at 80 mm (3.1 in) across 16 days, suggesting a wetter climate as winter transitions into spring. For more details, you can refer to the link: Dundalk weather in March.
September and April present quite different weather experiences. In September, temperatures range from a minimum of 3°C (37°F) to a pleasant average of 13°C (56°F), peaking at a maximum of 22°C (72°F). The month sees 74 mm (2.9 in) of precipitation over about 13 days, contributing to a relatively humid environment with 86% humidity. In contrast, April starts colder, with minimum temperatures dipping to -2°C (28°F) and an average of 8°C (47°F), while the maximum reaches 20°C (68°F). Precipitation is lighter, totaling 45 mm (1.8 in) across 11 days, with humidity slightly lower at 85%. For more details on April weather, check out Dundalk weather in April.
When comparing the weather in September and May, one can observe distinct seasonal differences. September typically presents milder temperatures, with an average of 13°C (56°F) and maximums reaching 22°C (72°F), while May, though slightly cooler with an average of 11°C (53°F), can still reach similar highs of 23°C (73°F). Precipitation levels are relatively similar, with September receiving 74 mm (2.9 in) over about 13 days and May slightly less at 66 mm (2.6 in) across 12 days. However, September tends to be more humid, averaging 86% compared to May's 83%. For more specific details about May weather patterns, you can check Dundalk weather in May.
In comparing the weather conditions of September and June, both months exhibit mild temperatures, but June tends to be warmer overall. In September, temperatures range from a minimum of 3°C (37°F) to a maximum of 22°C (72°F), with an average of 13°C (56°F). In contrast, June sees slightly higher temperatures, with a minimum of 4°C (40°F) and a maximum reaching up to 28°C (82°F), averaging 14°C (58°F). Precipitation levels are nearly identical, with September experiencing 74 mm (2.9 in) over 13 days and June slightly higher at 76 mm (3.0 in) over 14 days. Humidity remains similar, with September at 86% and June at 85%. For more detailed information on June weather, you can refer to Dundalk weather in June.
In September, temperatures begin to cool, with a minimum of 3°C (37°F) and an average of 13°C (56°F), peaking at 22°C (72°F). In contrast, July enjoys warmer conditions, with minimum temperatures at 7°C (45°F) and an average of 16°C (61°F), reaching a maximum of 28°C (82°F). Both months experience the same amount of precipitation at 74 mm (2.9 in) over 13 days, yet September's cooler temperatures mark a distinct shift in the season. Humidity levels remain consistent at 86% in both months, contributing to a damp atmosphere, particularly noticeable as summer transitions into autumn. For more detailed information on July's climate, you can check out Dundalk weather in July.
In comparing the weather between August and September, September tends to be cooler, with average temperatures ranging from a minimum of 3°C (37°F) to a maximum of 22°C (72°F), contrasted with August's milder range of 7°C (44°F) to 23°C (74°F). Additionally, September experiences more frequent rainfall, totaling 74 mm (2.9 in) over 13 days, compared to August's 114 mm (4.5 in) over 18 days. Humidity levels are fairly similar, with September at 86% and August slightly lower at 85%. For a detailed overview of the previous month's weather, you can visit Dundalk weather in August.
September and October exhibit a noticeable shift in weather patterns. While September boasts a milder average temperature of 13°C (56°F) and maximums reaching 22°C (72°F), October sees a drop in average temperature to 10°C (51°F) and peaks at 19°C (66°F). Precipitation also increases slightly in October, totaling 80 mm (3.1 in) over 14 days, compared to September's 74 mm (2.9 in) over 13 days. Additionally, humidity remains high in both months, with October slightly surpassing September at 87%. For more details, check out the Dundalk weather in October.
In September, the weather is generally milder, with average temperatures ranging from a low of 3°C (37°F) to a maximum of 22°C (72°F). The month experiences about 74 mm (2.9 in) of precipitation over 13 days, while humidity remains relatively high at 86%.
In contrast, November brings cooler temperatures, with averages between -3°C (27°F) and 15°C (59°F), and an increased chance of rain, totaling 84 mm (3.3 in) over 15 days. Despite the drop in temperature, humidity continues to hover around 86%. For more detailed information, you can check Dundalk weather in November.
September and December exhibit notably contrasting weather patterns. In September, temperatures range from a mild 3°C (37°F) at night to a pleasant 22°C (72°F) during the day, with an average of 13°C (56°F). This month experiences about 74 mm (2.9 in) of rain across 13 days while maintaining high humidity levels at 86%. In contrast, December sees cooler temperatures, with nighttime lows dropping to -3°C (27°F) and daytime highs peaking at 13°C (56°F), averaging around 6°C (43°F). Although December has slightly more precipitation at 89 mm (3.5 in) over the same number of rainy days, the humidity is marginally lower at 84%. For more details about December weather, check Dundalk weather in December.
September in Dundalk ushers in a noticeable shift in weather, marking a transition from the warmth of summer to the cooler embrace of autumn. While daytime temperatures can still reach a pleasant 22°C, the average drops to a cooler 13°C, and nighttime lows remind us that the chill is on its way. This month also sees a marked increase in precipitation, with rain gracing 13 days, contributing to the lush landscapes characteristic of this time of year. Coupled with the humidity hovering around 86%, September brings a unique blend of mild warmth and refreshing moisture. For those curious about the overall climate trends and how Dundalk's weather fluctuates throughout the year, check out Dundalk Climate.