September Weather in Sandymount, Ireland

Last updated: March 17, 2025

In September, Sandymount, Ireland experiences a pleasant transition into autumn, with temperatures ranging from a crisp 3°C (38°F) to a comfortable 22°C (72°F), averaging around 13°C (56°F). The month is characterized by significant rainfall, accumulating to 73 mm (2.9 in) over 14 days, contributing to a relatively high humidity level of 86%. As the leaves begin to change, this lovely seaside locale offers a refreshing backdrop, ideal for those seeking a mix of mild weather and the charm of early fall.

September Temperature in Sandymount

In September, Sandymount experiences a pleasant transition into autumn, with temperatures gradually dropping but still retaining a hint of summer. The minimum temperature hovers around 3°C (38°F), while the average climbs to a comfortable 13°C (56°F). This month witnesses a peak temperature of 22°C (72°F), ideal for enjoying the lingering warmth and the vibrant hues of autumn. As September unfolds, the days become shorter, yet the climate remains inviting, making it a beautiful time to explore the scenic landscapes and coastal charm of this picturesque Irish locale.

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

The chart illustrates September temperature patterns in Sandymount, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec424344475257605956514643
Data source: Temperature data for Sandymount 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 Sandymount

September in Sandymount, Ireland, typically brings 73 mm (2.9 in) of precipitation, falling on an average of 14 days. As summer transitions into autumn, the rainfall slightly decreases from the previous month’s higher total of 95 mm (3.8 in) in August. This decrease reflects a trend where the wetter months of mid-summer give way to a relatively drier September. Despite this dip, rainfall remains consistent, keeping the landscape lush and vibrant as the days shorten. The persistent drizzle characteristic of early autumn sets a picturesque backdrop, inviting both locals and visitors to enjoy the serene beauty of Sandymount as it transforms with the changing seasons.

September Precipitation Trends in Sandymount

The chart displays monthly precipitation patterns in Sandymount, 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.
JanFebMarAprMayJunJulAugSepOctNovDec578081527275809573879794
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Sandymount

In Sandymount, Ireland, the month of September is characterized by a humidity level of 86%, consistent with the slightly elevated figures observed throughout the summer months. This level is mirrored in both July and August, suggesting a seasonal trend where high humidity prevails as warmer weather sets in. Notably, September maintains a humidity that matches that of earlier months like March and February, showcasing the region's tendency towards moisture retention in the latter part of the year. As autumn approaches, the humidity is anticipated to rise slightly, reaching 87% in October, before gradually declining as winter draws near.

September Average Humidity in Sandymount

This chart illustrates the average monthly humidity levels in Sandymount, 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.
JanFebMarAprMayJunJulAugSepOctNovDec85%86%86%85%83%85%86%85%86%87%87%84%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Sandymount

As summer fades into early autumn in Sandymount, the UV Index experiences a notable shift. September marks a transition, with the UV Index dropping to 5, categorizing exposure as moderate and extending the burn time to 30 minutes. This is a slight decrease from the very high levels seen in July and June, where a score of 8 demanded more caution. Overall, September’s UV levels encourage outdoor enjoyment while reminding residents to remain mindful of sun protection. For more detailed information, visit Sandymount UV Index.

Maximum UV Index Levels in Sandymount for September

The chart shows the monthly maximum UV Index (UVI) for Sandymount 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.
JanFebMarAprMayJunJulAugSepOctNovDec124578875321
Data source: Sandymount 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 Sandymount

As September unfolds in Sandymount, Ireland, it brings a beautiful transition into autumn with 294 hours of sunshine, marking a delightful continuation of the vibrant summer months. This increase from the earlier months is reflective of a seasonal trend, rising from a modest 83 hours in January to a peak of 391 hours in May, before gradually tapering off. The long summer days make way for the crispness of fall, yet September still enjoys ample sunlight, significantly more than the dreary winter months ahead with just 120 hours in November. This balance of light highlights Sandymount's unique charm, as residents and visitors alike bask in the warmth of early autumn days before winter settles in.

Monthly Sunshine Duration in Sandymount: September Highlighted

The September sunshine duration represents the total number of hours Sandymount 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.
JanFebMarAprMayJunJulAugSepOctNovDec83h147h191h311h391h385h385h339h294h230h120h95h
Data source: Sandymount September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Sandymount During September

In Sandymount, Ireland, the likelihood of sunny weather tends to fluctuate throughout the year, with September showing a modest chance of 20% sunny days. As summer fades, sunshine becomes less frequent, following a pattern established in the preceding months. Notably, the sunniest months occur in April (44%) and dip again during the late summer, with August having a 23% chance. The trend indicates that while September offers a dwindling opportunity for sunshine, the warmth and brightness of summer linger in the memory, even as the chance of clear skies diminishes heading into autumn.

Percentage of Sunny Days in September in Sandymount

The chart illustrates the percentage of sunny days in Sandymount 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 Sandymount experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec23%21%22%44%31%24%30%23%20%19%26%23%
Data source: Sandymount September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Sandymount in September

As summer wanes in Sandymount, Ireland, September ushers in a subtle yet noticeable transition in daylight, with the sun gracing the sky for approximately 12 hours each day. This represents a gentle decline from the peak of 16 hours in June and July, as the days gradually shorten towards autumn. Following a vibrant summer, the balance of light and shadow begins to shift, preparing the landscape for the rich colors of fall. The rhythm of day and night continues its annual dance, falling to 10 hours by October, yet September's remaining daylight still invites outdoor adventures under the mellow sun. Each hour of light beckons residents and visitors alike to enjoy the lingering warmth before the longer nights draw in.

Average Daylight Hours in Sandymount for September

The chart illustrates the variation in daylight duration in Sandymount throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 7m9h 49m11h 54m14h 2m15h 54m16h 53m16h 22m14h 40m12h 37m10h 30m8h 36m7h 34m
Data source: Sandymount daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Sandymount

As summer wanes and autumn approaches, September in Sandymount brings a gentle breeze, with average wind speeds settling at a mild 3.4 m/s (8 mph). This slight drop in wind intensity follows the more vibrant gusts of summer, peaking in July with only 2.7 m/s (6 mph), illustrating a season of relative calm. Compared to the brisk October and November months, where the winds pick up again to around 4.9 m/s (11 mph), September offers a transitional breath—a moment where the warmth of late summer lingers in the air, even as the promise of autumn begins to unfold. Overall, September’s moderate winds create a fitting backdrop for the changing landscape, inviting a sense of both serenity and anticipation for the vibrant colors of fall.

Average September Wind Speed in Sandymount

The chart displays monthly wind speed patterns in Sandymount, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.56.04.73.44.03.72.73.63.4 m/s4.94.84.9
Data source: Sandymount September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Sandymount Compares to Other Months

The weather in Sandymount 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 Sandymount and find detailed weather information for every month.

In September, the weather is generally milder, with temperatures ranging from a minimum of 3°C (38°F) to a maximum of 22°C (72°F) and an average of 13°C (56°F). The month experiences significant precipitation, with about 73 mm (2.9 in) over 14 days, and a high humidity of 86%. In contrast, January brings much colder conditions, where temperatures typically range from -3°C (26°F) to 13°C (56°F), averaging around 5°C (42°F). Precipitation is somewhat lower at 57 mm (2.2 in) over 10 days, with humidity remaining slightly lower at 85%. For more on January's climate, you can check Sandymount weather in January.

September and February present distinct weather patterns, reflecting the transition from late summer to winter. In September, temperatures range from a minimum of 3°C (38°F) to a maximum of 22°C (72°F), with an average of 13°C (56°F). This month experiences 73 mm (2.9 in) of precipitation over 14 days, all while maintaining a high humidity level of 86%. In contrast, February sees cooler temperatures, with a minimum of -2°C (29°F), an average of 6°C (43°F), and a maximum of 14°C (58°F). Precipitation slightly increases to 80 mm (3.1 in) over the same number of days, yet humidity remains consistent at 86%. For a more detailed look at February weather, you can check Sandymount weather in February.

In comparing the weather between September and March, it is evident that March tends to be cooler with a minimum temperature of -5°C (24°F) compared to September's minimum of 3°C (38°F). The average temperatures also reflect this difference, with September averaging 13°C (56°F) versus March's 7°C (44°F). Additionally, September experiences a higher maximum temperature of 22°C (72°F), while March peaks at 16°C (61°F). Precipitation levels are fairly similar, with March receiving 81 mm (3.2 in) over 15 days compared to September's 73 mm (2.9 in) over 14 days. Both months share the same humidity level of 86%. For a closer look at March weather specifics, check out Sandymount weather in March.

When comparing the weather in September and April, we see notable differences in temperature and precipitation. September tends to be milder, with temperatures ranging from 3°C (38°F) to a maximum of 22°C (72°F), while April is cooler, with temperatures dropping as low as -2°C (29°F) and peaking at 19°C (66°F). Precipitation is slightly higher in September, with 73 mm (2.9 in) over about 14 days, compared to April's 52 mm (2.0 in) over 11 days. Both months exhibit similar humidity levels, with September at 86% and April at 85%. For those interested in exploring April's weather in more detail, you can find additional information here: Sandymount weather in April.

When comparing the weather in September and May, both months exhibit similar average temperatures and precipitation levels, but there are noteworthy differences in their characteristics. In September, the temperatures range from a chilly minimum of 3°C (38°F) to a comfortable maximum of 22°C (72°F) with an average of 13°C (56°F). The month is relatively humid at 86%, and experiences about 14 days of precipitation, totaling 73 mm (2.9 inches).

In contrast, May starts off with cooler temperatures, with a minimum of 0°C (32°F) and an average high of 21°C (71°F), culminating in an overall average of 11°C (52°F). Precipitation is slightly less at 72 mm (2.8 inches) over the same number of rainy days, and the humidity is marginally lower at 83%. This makes September feel warmer overall despite having similar levels of rainfall. For a closer look at weather patterns during this month, you can check Sandymount weather in May.

In comparing the weather of September and June, we see some notable differences. September boasts a minimum temperature of 3°C (38°F) and an average of 13°C (56°F), while June starts at a slightly warmer minimum of 6°C (42°F) and has an average of 14°C (57°F). The maximum temperatures in June reach up to 24°C (75°F), compared to September's maximum of 22°C (72°F). Precipitation levels are fairly similar, with September receiving 73 mm (2.9 in) over 14 days and June slightly higher at 75 mm (3.0 in) across 15 days. Both months experience high humidity, but September is marginally more humid at 86% compared to June's 85%. For more specific weather details, check out Sandymount weather in June.

When comparing the weather in September and July, notable differences emerge. September experiences cooler temperatures, with a minimum of 3°C (38°F) and a maximum of 22°C (72°F), averaging around 13°C (56°F). In contrast, July tends to be warmer, featuring a minimum of 8°C (46°F) and a maximum of 25°C (77°F), with an average temperature of 16°C (60°F). Precipitation levels are somewhat similar, with September receiving 73 mm (2.9 in) over 14 days compared to July's 80 mm (3.2 in) during the same number of days. Notably, humidity remains consistent at 86% in both months. For more detailed information on July weather in Sandymount, you can visit Sandymount weather in July.

In comparing the weather of September and August, September tends to be cooler, with average temperatures ranging from a minimum of 3°C (38°F) to a maximum of 22°C (72°F), while August has slightly warmer temperatures, with a minimum of 7°C (45°F) and a maximum of 23°C (73°F). Precipitation is more frequent in August, occurring on 16 days and totaling 95 mm (3.8 in), compared to September's 73 mm (2.9 in) over 14 days. Humidity levels remain similar throughout both months, with September experiencing a slight increase at 86%, compared to August's 85%. For more detailed insights, you can check Sandymount weather in August.

In comparing the weather of September and October, we observe a marked cooling trend as we transition into autumn. September boasts a minimum temperature of 3°C (38°F) with an average of 13°C (56°F) and a maximum of 22°C (72°F), while October sees temperatures dropping further, recording a minimum of 1°C (35°F) and an average of 11°C (51°F), peaking at 18°C (65°F). Both months experience similar levels of rainfall, with September having 73 mm (2.9 in) and October slightly higher at 87 mm (3.4 in), yet both registering precipitation on 14 days. Humidity remains quite consistent, with September at 86% and October slightly up at 87%. For more detailed information on the weather in October, you can visit Sandymount weather in October.

In comparing the weather between September and November, September tends to be slightly warmer with average temperatures ranging from 3°C (38°F) to a maximum of 22°C (72°F), while November sees cooler averages with temperatures ranging from 0°C (32°F) to a maximum of 15°C (59°F). Both months experience a similar level of humidity at 86%; however, November has a higher total precipitation of 97 mm (3.8 in) compared to September's 73 mm (2.9 in), albeit over the same number of days with rain (14). For more specific details about November weather, you can check Sandymount weather in November.

September and December exhibit notable differences in weather characteristics. In September, temperatures range from a mild 3°C (38°F) to a comfortable maximum of 22°C (72°F), with an average of 13°C (56°F). The month experiences 73 mm (2.9 in) of precipitation over 14 days, coupled with high humidity at 86%. In contrast, December brings cooler temperatures, with a minimum of -2°C (28°F) and a maximum of 13°C (56°F), averaging at 6°C (44°F). The precipitation increases slightly to 94 mm (3.7 in) across 15 days, while humidity remains relatively stable at 84%. These changes mark a transition from the warmer, more humid days of early autumn to the colder, wetter conditions of midwinter. For more detailed insights, you can check Sandymount weather in December.

Compare Sandymount's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Sandymount

As summer transitions into autumn, September in Sandymount presents a unique blend of mild temperatures and increased rainfall. While the days can still be pleasantly warm, averaging around 13°C, they also hint at the chill of the months to come. This month typically sees a rise in precipitation with significant humidity, resulting in more cloudy and rainy days than in prior months. The mix of lingering warmth and the onset of dampness makes September a season of change, inviting visitors to experience the beautiful, evolving landscape of Sandymount. For more insights into the full range of weather patterns, be sure to check out Sandymount Climate.