Last updated: March 17, 2025
September in Caerphilly, United Kingdom brings a blend of warm days and cool evenings, with temperatures ranging from a refreshing 4°C (40°F) at night to a pleasant 27°C (81°F) during the day. The average temperature hovers around a comfortable 15°C (59°F). While the month showcases beautiful early autumn scenery, it also comes with 81 mm (3.2 in) of rainfall over 12 days, contributing to a humidity level of 79%. Whether you're enjoying the surprisingly warm afternoons or preparing for drizzly spells, September in Caerphilly offers a captivating weather experience.
As September rolls in Caerphilly, the weather transitions into a mild and inviting phase, marking the tail end of summer. With min temperatures settling around 4°C (40°F) and peaking at an average of 15°C (59°F), the air carries a pleasant warmth that encourages outdoor adventures. Daytime highs can reach an impressive 27°C (81°F), echoing the lingering summer vibes. This month stands out as a delightful blend of warmth and cool breezes, making September a unique time in the region as it gently shifts towards the autumn chill, bringing about vivid foliage and crisp evenings.
In September, Caerphilly experiences a moderate precipitation level with 81 mm (3.2 in) of rainfall spread over 12 days. This rainfall amount, while notable, sits comfortably within the average parameters for the late summer season, continuing the trend observed from August's 97 mm (3.8 in). As autumn approaches, the frequency of rainy days begins to increase, foreshadowing the wetter months ahead, particularly as October typically sees a substantial uptick to 135 mm (5.3 in). Overall, September serves as a transition point, hinting at the seasonal shifts while maintaining a balanced level of moist weather.
As September arrives in Caerphilly, the humidity reflects a gradual decline from the summer months, settling at 79%. This is a noteworthy shift when compared to the higher humidity levels of August's 73% and an even more significant drop from the peak of 88% seen in the chill of January and February. The trends indicate a slow transition into autumn, where humidity begins to creep back up towards winter levels, peaking again at 89% in October and November. It's clear that the seasons play a crucial role in shaping the humidity landscape, with September serving as a gentle bridge between the warmth of summer and the crispness of autumn.
As summer winds down in Caerphilly, September presents a UV Index of 6, indicating a high exposure category with a burn time of just 25 minutes. This marks a transition from the blazing days of July and June, which boasted the highest UV levels at 8, to a slightly lower but still significant index. With the gradual drop in UV intensity, residents and visitors should remain vigilant about sun protection while enjoying the pleasant early autumn weather. The UVI trends throughout the year reflect a clear pattern: from the low levels in winter, the index peaks in mid-summer before tapering off in the fall. For more detailed information, check out the Caerphilly UV Index.
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September in Caerphilly, United Kingdom, brings a delightful interlude of sunshine, boasting 279 hours of sun, a marked shift from the sun-drenched peak of summer. Having basked in 399 hours of sunshine in July, the region slowly transitions into autumn with September's golden rays, which still provide a generous glow compared to the winter months ahead. The sun starts to wane compared to the vibrant summer, but this month's light is crucial, bridging the gap between the lush greens of summer and the crisp air of fall. As the days grow shorter, September’s warmth offers a gentle reminder of the sun-soaked days just passed, while hinting at the cozy, quieter months to come.
In Caerphilly, United Kingdom, September sees a 28% chance of sunny weather, marking a slight dip from the summer months. While July boasts the highest likelihood of sunshine at 41%, this favorable trend begins to wane as autumn approaches, with August trailing closely at 30%. By September, the weather turns notably less predictable, reflecting a typical transition into autumn, when residents can expect more variable conditions. Overall, while the sun still makes some appearances, it’s a reminder that summer is giving way to the more temperamental fall weather.
As summer gently yields to autumn in Caerphilly, September brings a notable shift in daylight, with the sun gracing the skies for approximately 12 hours each day. This marks a gentle decline from the 16 hours enjoyed during the peak of summer in June and July, gradually transitioning toward the shorter days of autumn. The month offers a comforting balance as daylight begins to fade, emphasizing the cozy charm of the approaching fall. With longer evenings, residents can delight in the vibrant colors of autumn while still savoring a generous amount of sunlight, bridging the gap between the lively summer and the serene winter months ahead.
As September rolls into Caerphilly, the average wind speed settles at a gentle 3.7 m/s (8 mph), reflecting a calming transition towards autumn. Following a summer marked by slightly breezier days, September's winds are akin to a soft whisper, offering relief from the warmer months. This dip in wind speed from a peak of 5.7 m/s (13 mph) in February suggests a gradual cooling trend as the seasons change. Observing the year in its entirety, September’s winds align closely with those of April and July, bridging the mild breezes of late summer with the crisp air of early autumn. Nature reminds us that with each season, a new rhythm emerges, inviting both the quietude and beauty of the changing landscape.
The weather in Caerphilly 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 Caerphilly and find detailed weather information for every month.
September and January showcase contrasting weather patterns. In September, temperatures fluctuate between a cool 4°C (40°F) at night and a warm 27°C (81°F) during the day, with an average of 15°C (59°F). This month experiences notable humidity at 79% and about 81 mm (3.2 in) of precipitation over 12 days. In contrast, January brings much colder conditions, with nighttime temperatures dropping to -3°C (27°F) and daytime highs reaching only 13°C (56°F), resulting in an average temperature of 6°C (42°F). The precipitation remains similar at 75 mm (3.0 in) over the same number of days but with a higher humidity level of 88%. For more detailed insights, check Caerphilly weather in January.
September tends to be milder and more variable compared to February, with temperatures ranging from a minimum of 4°C (40°F) to a maximum of 27°C (81°F) and an average of 15°C (59°F). In contrast, February experiences colder conditions, with temperatures peaking at 15°C (60°F) but dipping as low as -4°C (26°F), yielding an average of just 6°C (44°F). Additionally, February sees slightly more precipitation (101 mm or 4.0 in) spread over more days (14) than September, which receives 81 mm (3.2 in) across 12 days. The humidity in February is also higher, at 88%, compared to September's 79%. For a detailed look at the weather patterns, check out Caerphilly weather in February.
The weather in September presents a notable contrast to March, with September enjoying milder temperatures ranging from a minimum of 4°C (40°F) to a maximum of 27°C (81°F), and an average of 15°C (59°F). On the other hand, March sees cooler temperatures, with a minimum dipping to -5°C (22°F), an average of 7°C (45°F), and a maximum of 18°C (65°F). Furthermore, precipitation is slightly higher in March at 97 mm (3.8 in) over 15 days, compared to September's 81 mm (3.2 in) across 12 days. Humidity also tends to be higher in March at 86%, compared to September's 79%. For more details, you can check Caerphilly weather in March.
In comparing the weather patterns of September and April, September tends to be warmer, with average temperatures ranging from 4°C (40°F) to 27°C (81°F), while April experiences colder conditions, with temperatures ranging from -1°C (30°F) to 20°C (69°F). September also sees higher average temperatures, about 15°C (59°F), compared to April's average of 9°C (49°F). Additionally, while both months have a notable number of rainy days, September records more precipitation at 81 mm (3.2 in) over 12 days, compared to April's 57 mm (2.2 in) over 10 days. Humidity levels are slightly higher in April at 84%, while September maintains a humidity level of 79%. For a more detailed overview, you can check Caerphilly weather in April.
When comparing the weather in September and May, several key differences emerge. September typically experiences a wider range of temperatures, with a minimum of 4°C (40°F) and a maximum of 27°C (81°F), while May has slightly cooler temperatures, ranging from 2°C (35°F) to 24°C (76°F). Both months see similar levels of precipitation, with September recording 81 mm (3.2 in) and May receiving 79 mm (3.1 in), each spanning about 12 days of rain. Humidity levels are also comparable, with September at 79% and May at 80%. Overall, September feels warmer and has a bit more variability in temperature compared to the cooler and slightly more stable May weather. For more details, see Caerphilly weather in May.
September and June in Caerphilly present similar temperature ranges, with both months reaching a maximum of around 27°C (81°F) to 27°C (82°F). However, September tends to be slightly cooler overall, with minimum temperatures dropping to 4°C (40°F) compared to June's 7°C (45°F). Precipitation levels are closely matched, with September receiving 81 mm (3.2 in) and June slightly higher at 84 mm (3.3 in), both spread over approximately 12 days. Humidity remains consistent in both months, hovering around 79% in September and 80% in June. For a detailed look at June weather conditions, you can visit Caerphilly weather in June.
When comparing the weather in September and July, notable differences emerge. September experiences a wider temperature range, with a minimum of 4°C (40°F) and a maximum of 27°C (81°F), leading to an average of 15°C (59°F). In contrast, July's minimum is higher at 9°C (48°F), with a slightly cooler average of 17°C (63°F) and a maximum of 28°C (82°F). Both months receive a similar amount of precipitation, with September totaling 81 mm (3.2 in) and July slightly higher at 85 mm (3.3 in), both spread over 12 days. However, September tends to be more humid at 79%, compared to July's 70%. For a more detailed look at July weather specifics, you can check Caerphilly weather in July.
In comparing the weather between August and September, September experiences lower minimum and average temperatures, with a minimum of 4°C (40°F) and an average of 15°C (59°F), compared to August's minimum of 9°C (48°F) and average of 17°C (62°F). The maximum temperatures are also slightly lower in September, reaching up to 27°C (81°F) compared to August's 29°C (84°F). Precipitation is more frequent in September, occurring on 12 days with a total of 81 mm (3.2 in), while August has a bit more rain at 97 mm (3.8 in) over 13 days. Furthermore, September shows higher humidity levels at 79% compared to 73% in August. For a detailed look at August's weather patterns, you can visit Caerphilly weather in August.
As September transitions into October, the weather begins to notably shift. September features a broader temperature range with minimums around 4°C (40°F) and maximums reaching 27°C (81°F). The average temperature settles at a comfortable 15°C (59°F), accompanied by 81 mm of precipitation over 12 days and a relative humidity of 79%. In contrast, October sees a decline in temperatures, with minimums dropping to 1°C (33°F) and maximums peaking at 21°C (70°F), resulting in an average of 12°C (54°F). This month is also wetter, bringing 135 mm of rainfall over 16 days, and humidity increases to 89%. For more insights, you can check Caerphilly weather in October.
In September, the weather is generally warmer, with temperatures ranging from a minimum of 4°C (40°F) to a maximum of 27°C (81°F) and an average of 15°C (59°F). The month sees about 81 mm (3.2 in) of precipitation spread over 12 days, accompanied by a relatively comfortable humidity of 79%. In contrast, November brings a noticeable chill, with temperatures dropping to a minimum of -1°C (30°F) and reaching a maximum of 16°C (61°F), averaging around 9°C (48°F). Additionally, November is wetter, featuring approximately 99 mm (3.9 in) of precipitation over 15 days and higher humidity at 90%. For more specific details, you can check Caerphilly weather in November.
September and December present notably different weather patterns. In September, temperatures range from a low of 4°C (40°F) to a comfortable high of 27°C (81°F), with an average of 15°C (59°F). The month sees around 81 mm (3.2 in) of precipitation over approximately 12 days, coupled with a relatively moderate humidity of 79%. In contrast, December experiences chillier temperatures, with a minimum of -4°C (26°F), an average of 7°C (45°F), and a maximum of 13°C (56°F). This month also brings increased precipitation, totaling 130 mm (5.1 in) over about 17 days, along with higher humidity at 89%. For more on December weather specifics, visit Caerphilly weather in December.
As September unfolds in Caerphilly, the weather presents a unique transition into autumn, contrasting sharply with the warmth of the summer months. With temperatures averaging around 15°C while occasionally reaching a maximum of 27°C, the days can still feel pleasantly warm. However, cooler nights remind us that summer is giving way to fall, sometimes dropping to a brisk 4°C. Rain becomes more frequent, with about 12 days of precipitation bringing roughly 81 mm of moisture, contributing to a humid atmosphere that averages 79%. This blend of lingering warmth and increasing rainfall makes September a month of change, encouraging both outdoor adventures and cozy indoor retreats. For a deeper dive into the yearly weather patterns, check out Caerphilly Climate.