Last updated: March 17, 2025
September in Swansea, United Kingdom, showcases a dynamic blend of weather patterns, with a maximum temperature reaching 24°C (76°F) and an average of 15°C (60°F), while dipping to a minimum of 9°C (48°F). Amidst this variability, the city experiences moderate rainfall, totaling 120 mm (4.7 in) across approximately 15 days, contributing to a humidity level of 79%. This combination of mild temperatures and frequent showers creates an environment ideal for enjoying the lush landscapes and vibrant scenery that Swansea has to offer, making it a captivating month for both locals and visitors alike.
As September settles over Swansea, the city experiences a gentle transition towards autumn. Temperatures begin to cool, with minimums averaging around 9°C (48°F) and maximums peaking at 24°C (76°F). This month strikes a pleasant balance, featuring an average temperature of 15°C (60°F), reminiscent of the warmer summer days while hinting at the crispness to come. Compared to the preceding months, September holds onto the warmth but marks a notable drop from the sweltering highs of July and August. This shift invites charming walks along Swansea’s coast, as the rich hues of fall foliage begin to emerge, creating an inviting and picturesque atmosphere.
In September, Swansea experiences a notable transition as summer gives way to autumn, marked by an average precipitation of 120 mm (4.7 in) spread across 15 days of rain. This month holds steady with a significant amount of rainfall, closely mirroring the wetter months of August and October, which see 123 mm and 184 mm respectively. Not only does this highlight a persistent pattern in rainfall as the year approaches its end, but it also suggests that residents should prepare for the moody, overcast days typical of Welsh autumns. The consistent rainfall throughout the summer months gradually sets the stage for the season's shifts, inviting vibrant autumn hues while maintaining a rhythm of drizzles and downpours that characterize Swansea's climate.
As autumn begins to set in, September in Swansea experiences a noticeable shift in humidity, with levels averaging around 79%. This reflects a slight increase from the summer months, where July and August recorded lower levels at 70% and 73%, respectively. Notably, the transition from summer to fall marks a gradual rise in humidity, aligning with the trends witnessed earlier in the year. The historical data shows that humidity reaches its peak during the winter months, with January and February averaging a high 88%. Overall, September serves as a pivotal moment when humidity starts its ascent towards the wetter months ahead, preparing Swansea for the rain that often characterizes the later part of the year.
As summer transitions to autumn, September in Swansea reveals a UV Index of 6, indicating a high exposure level. This marks a slight decline from the intense summer months, where the index peaked at 8 in both June and July. Despite the drop, sun seekers should still be cautious, as the recommended burn time remains at 25 minutes—the same as in August, which also had a high index. This trend suggests that while the sun's intensity is waning, vigilance is still necessary for outdoor activities. Keep this in mind as you enjoy the beautiful Welsh scenery—it's essential to protect your skin! For more detailed information on UV levels, visit Swansea UV Index.
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September in Swansea marks a tranquil transition from the vibrant summer months to the crispness of autumn. After basking in over 400 hours of sunshine during the peak summer, the city experiences a gentle decline to 309 hours in September. This remaining sunshine serves as a comforting farewell to the warmer days, as daylight begins to wane. Comparatively, while September shines brighter than the gloomy winter months, it still reflects a significant decrease from the summer zenith. The moderate sunshine invites locals and tourists alike to relish the beautiful early fall landscapes, making it an ideal time for outdoor activities and scenic strolls along the picturesque coastline.
As September rolls into Swansea, the chances of encountering sunny weather stand at 28%, suggesting a moderate likelihood of clear skies. This percentage marks a slight dip compared to the summer months, with August boasting a 34% chance and July peaking at 42%. Interestingly, September continues a trend seen in earlier months like June and May, where optimism for sunshine wanes as autumn approaches. However, the sun's presence is still more pronounced than the gloomier days of winter, evident in the drop to 22% in October. Thus, while September may not promise consistent sunshine, it still offers a fair chance to enjoy the lingering warmth of summer before the seasonal shift.
As summer transitions into autumn, September in Swansea sees a decrease in daylight duration, offering around 12 hours of light each day. This shift marks a notable change after the sun-soaked months of June and July, where the city basked in a generous 16 hours of daylight. As the days shorten, September remains a sweet spot of moderate light, standing between the vibrant summer and the deeper twilight of October. Following the lively blooms of spring and the sunlit joys of summer, this month serves as a gentle reminder of nature’s rhythm, gracefully easing residents into autumn's cozy embrace.
As summer fades away, September in Swansea brings a gentle shift in the winds. With an average wind speed of 4.7 m/s (10 mph), the breezes are noticeably calmer compared to the summer months, echoing the trend from June and July. This drop complements the arrival of autumn, where the winds become softer, inviting a more leisurely pace as the city transitions into the cooler season. Interestingly, as we move towards October, a notable uptick in wind speed occurs, hinting at the seasonal changes ahead. The ebb and flow of the wind throughout the year remind us of nature's rhythms, with September marking a serene pause before the gusts of autumn truly begin.
The weather in Swansea 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 Swansea and find detailed weather information for every month.
In September, the weather is generally milder, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 24°C (76°F) and an average temperature of 15°C (60°F). During this month, rainfall is relatively high at 120 mm (4.7 in) over approximately 15 days, while humidity averages around 79%. In contrast, January brings cooler temperatures, with a range from 0°C (32°F) to 14°C (57°F) and an average of just 7°C (45°F). Despite having slightly lower precipitation at 106 mm (4.2 in) over 14 days, January is marked by higher humidity levels of 88%. For more detailed information, you can check Swansea weather in January.
In September, temperatures range from a mild 9°C (48°F) at night to a warm 24°C (76°F) during the day, offering an average of 15°C (60°F). The month sees about 120 mm (4.7 in) of precipitation spread over 15 days, with a humidity level of 79%. In contrast, February is significantly colder, with temperatures dipping to a minimum of -1°C (30°F) and only reaching a maximum of 13°C (55°F), resulting in an average of 7°C (45°F). Precipitation slightly increases to 128 mm (5.0 in) over 17 days, accompanied by higher humidity at 88%. For more detailed weather information, you can check Swansea weather in February.
In comparing the weather between September and March, we can observe notable differences. September tends to be milder, with average temperatures ranging from a minimum of 9°C (48°F) to a maximum of 24°C (76°F), while March experiences chillier conditions, with temperatures ranging from a minimum of -4°C (25°F) to a maximum of 15°C (59°F). Both months witness substantial precipitation, although September has slightly more rainfall at 120 mm (4.7 in) over 15 days compared to March's 114 mm (4.5 in) over 18 days. Additionally, humidity levels are higher in March, reaching 86%, compared to 79% in September. For a more detailed look at what to expect in March, you can visit Swansea weather in March.
September and April present contrasting weather patterns, with September generally being warmer and wetter. In September, temperatures range from a minimum of 9°C (48°F) to an average of 15°C (60°F), peaking at 24°C (76°F), while April experiences cooler temperatures, with a minimum of 2°C (36°F), an average of 9°C (49°F), and a maximum of 17°C (63°F). Additionally, September sees more precipitation, totaling 120 mm (4.7 in) over approximately 15 days, compared to April's 56 mm (2.2 in) over 9 days. Despite September's slightly lower humidity at 79%, it remains quite humid, similar to April's 84%. For more specific insights into April weather, you can refer to Swansea weather in April.
When comparing the weather in September and May, September generally offers warmer temperatures with a minimum of 9°C (48°F) and an average of 15°C (60°F), while May’s temperatures range from a minimum of 5°C (40°F) and an average of 12°C (53°F). September also features more significant rainfall, with a total precipitation of 120 mm (4.7 in) over 15 days, compared to May's 79 mm (3.1 in) over 11 days. Both months experience similar humidity levels, with September at 79% and May slightly higher at 80%. For more detailed insights, you can check Swansea weather in May.
In comparing the weather of September and June, both months exhibit similar temperature ranges, with minimums around 9°C (48°F), averages close to 15°C (59-60°F), and maximums reaching 24°C (76°F). However, September tends to be slightly wetter, receiving 120 mm (4.7 in) of precipitation over 15 days, compared to June, which has 93 mm (3.6 in) of rain over the same number of days. The humidity levels are quite comparable, with September at 79% and June at 80%. For more detailed insights, you can visit Swansea weather in June.
In comparing the weather of September and July, we see distinct differences in temperature and precipitation patterns. September experiences slightly cooler temperatures, with averages ranging from a minimum of 9°C (48°F) to a maximum of 24°C (76°F), while July has a warmer average, with minimums around 11°C (52°F) and the same maximum of 24°C (76°F). Additionally, September is wetter, facing 120 mm (4.7 in) of precipitation over 15 days compared to July's 91 mm (3.6 in) over 13 days. Humidity levels are also higher in September, averaging 79%, compared to 70% in July. For more detailed information, you can check the Swansea weather in July.
In comparing the weather between August and September, we see a noticeable decline in minimum temperatures, with September starting at a low of 9°C (48°F) compared to August's 12°C (53°F). While the average maximum temperatures remain similar at around 24°C (76°F) in both months, September's average temperature drops to 15°C (60°F), indicating a cooling trend as summer transitions into autumn. Precipitation levels are slightly lower in September at 120 mm (4.7 in) over 15 days, whereas August experiences 123 mm (4.8 in) over 18 days, showing that while rain is common in both months, Sunday is somewhat drier. Furthermore, humidity is higher in September at 79%, compared to August's 73%, contributing to a more humid feel as the season shifts. For those interested in the specifics of August weather, further details can be found here: Swansea weather in August.
September and October exhibit notable changes in weather patterns. In September, temperatures range from a minimum of 9°C (48°F) to a maximum of 24°C (76°F), with an average of 15°C (60°F) and 120 mm (4.7 in) of precipitation over approximately 15 days. Humidity sits at a moderate 79%. In contrast, October brings cooler temperatures, with a minimum of 3°C (38°F) and a maximum of 20°C (68°F), averaging 13°C (55°F). This month is also wetter, seeing 184 mm (7.2 in) of precipitation across 19 days, and a higher humidity level of 89%. For more detailed information, check out Swansea weather in October.
In comparison to September, November experiences noticeably cooler temperatures, with a minimum of 2°C (35°F) and an average of 10°C (50°F), compared to September's minimum of 9°C (48°F) and average of 15°C (60°F). The maximum temperature in November reaches only 16°C (60°F), significantly lower than September's maximum of 24°C (76°F). Additionally, November sees an increase in precipitation, totaling 143 mm (5.6 in) over 19 days, compared to September's 120 mm (4.7 in) across 15 days. Humidity levels also rise in November, reaching 90% versus September's 79%, contributing to a much wetter and chillier feel. For more detailed information, check out Swansea weather in November.
In September, the weather is relatively mild with average temperatures ranging from a cool 9°C (48°F) to a pleasant maximum of 24°C (76°F), while experiencing about 120 mm (4.7 in) of precipitation over approximately 15 days. The humidity sits at a comfortable 79%, making it a transition month into the cooler fall season. In contrast, December sees a significant drop in temperatures, with averages hovering around 2°C (35°F) to a maximum of 13°C (55°F). The precipitation increases to 184 mm (7.3 in), spread over 21 days, resulting in a more damp environment with higher humidity levels at 89%. For more detailed insights, visit Swansea weather in December.
As September unfolds in Swansea, it marks a transition into the cooler embrace of autumn, with temperatures averaging around 15°C and a notable humidity level of 79%. While the month can still see a maximum of 24°C, it is also characterized by an increase in rainfall, averaging 120 mm over roughly half the month with about 15 days of precipitation. This shift brings a refreshing chill to the air, contrasting with the warmth of summer, and hints at the cozy, vibrant atmosphere of the coming fall. For more insights into how Swansea’s weather transitions throughout the year, be sure to check out Swansea Climate.