Last updated: February 24, 2025
September in Southampton, United States, offers a delightful transition into autumn, with average temperatures hovering around 20°C (69°F). The month experiences a pleasant maximum of 27°C (81°F), ideal for outdoor activities, while evenings cool down to a minimum of 12°C (55°F). Residents and visitors should be prepared for some moisture, as rainfall accumulates to 97 mm (3.8 in) over approximately 10 days, contributing to a humidity level of 68%. This blend of warmth and occasional showers creates a refreshing backdrop, perfect for experiencing the beauty of early fall in this charming locale.
In September, Southampton experiences a delightful transition into early autumn, with temperatures showcasing a mild range. The minimum temperature settles at 12°C (55°F), while the average climbs to a comfortable 20°C (69°F), reaching a pleasant maximum of 27°C (81°F). This marks a noticeable shift from the summer heat of August, where highs lingered around 28°C (83°F). As the month progresses, the warmth begins to ebb, signaling the approach of cooler days ahead. Overall, September offers a perfect blend of warmth and crispness, making it an ideal time for outdoor activities and enjoying the changing leaves.
In September, Southampton experiences a moderate precipitation level of 97 mm (3.8 in), mirroring the wetness of the summer months while remaining below the dramatic increases typical of October. Rainfall occurs across 10 days, maintaining a consistent pattern seen throughout the month. This steady precipitation marks September as a transitional phase, bridging the lighter summer rains of June and August and the more substantial downpours expected in the approaching autumn. As the year progresses, it's evident that September plays a crucial role in setting the stage for the wetter months ahead.
September in Southampton, United States, marks a transitional point in humidity levels, with a slight rise to 68% after the drier months of summer. This increase reflects a shift from the more enjoyable, lower humidity levels of July and August, which recorded 62% and 65%, respectively. As the region prepares for the fall, humidity begins to climb again, following the pattern observed in earlier months. This fluctuation signifies not just the end of summer's warmth but also foreshadows the wetter conditions typical of autumn. In fact, as the year progresses into October, humidity is expected to reach 74%, indicating that Southampton residents can anticipate a return to the more humid conditions reminiscent of winter months, when humidity spikes back to 82% in November.
In September, Southampton experiences a UV Index of 8, categorizing the exposure as very high with a burn time of just 15 minutes. This indicates a slight decrease from the peak summer months, where July and June boasted a maximum index of 10. As autumn approaches, while the UV levels begin to moderate, it's still crucial for residents and visitors to take protective measures against UV radiation. The trend shows that, from March through September, UV levels climb significantly, peaking in the summer months, reminding us to stay vigilant about sun safety throughout the warmer season. For more detailed information, visit Southampton UV Index.
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In September, Southampton basks in a delightful 281 hours of sunshine, marking a gentle transition from the summer's peak. This month follows July's sun-drenched high of 349 hours and August's still strong 327 hours, reflecting an overall trend of glorious summer days. As autumn begins to weave its way into the tapestry of the year, the sunlight gradually softens, yet September retains a robust amount of brightness compared to the earlier months. With sunshine hours steadily decreasing as the year winds down—most notably to 229 hours in October and 177 hours by December—September remains a cherished time to enjoy the outdoors before the chill sets in. The rhythm of the seasons is palpable, inviting residents and visitors alike to savor the last golden days of summer.
In September, Southampton experiences a 49% chance of sunny weather, maintaining a relatively steady outlook from the preceding months. This percentage is comparable to spring, where March and April show slightly higher probabilities of sunshine. Interestingly, as summer comes to a close, the sunny prospects in September edge out the less favorable conditions seen in August (34%) but align closely with what residents can expect in October (45%). Overall, September strikes a balance, hinting that while not guaranteed, sunny days are definitely in the cards as the region transitions into fall.
As summer gracefully transitions into fall, September in Southampton offers a delightful balance with 12 hours of daylight. Following the sun-drenched days of June and July, where daylight peaked at 15 hours, this month signals the beginning of shorter days. The gradual decrease in daylight, which starts in August, marks a shift towards the cozy embrace of autumn. This steady decline from the peak summer brightness reflects nature's rhythm, as the community prepares for the cooler months ahead. As the days grow shorter, residents can enjoy the rich hues of changing leaves, making September a beautiful prelude to the fall season.
As September rolls in, Southampton experiences a noticeable uptick in wind speed, averaging 5.8 m/s (13 mph). This marks a shift from the calm, languid days of summer, where winds dipped to 4.6 m/s (10 mph) in both July and August. The refreshing winds begin to herald the approaching fall, with October ushering in an increase to 6.4 m/s (14 mph). This gradual rise in wind speed, particularly noticeable after the summer months, suggests a transition towards the crisper conditions of autumn, making September a delightful time to enjoy the outdoors, as the breeze invigorates the idyllic landscape of Southampton.
The weather in Southampton 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 Southampton and find detailed weather information for every month.
September weather in Southampton is characterized by mild temperatures, with averages around 20°C (69°F) and highs reaching up to 27°C (81°F). The humidity hovers around 68%, and the month experiences moderate rainfall with about 97 mm (3.8 in) spread over 10 days. In contrast, January presents a stark contrast, with much cooler conditions where the average temperature drops to just 2°C (36°F) and nighttime lows can plunge to -13°C (8°F). While January sees slightly less precipitation at 90 mm (3.5 in) over 9 days, the humidity increases to 84%, making the cold feel more biting. For more details on January’s weather, check out Southampton weather in January.
September and February present strikingly different climates. In September, temperatures range from a mild 12°C (55°F) at night to a warm average of 20°C (69°F) during the day, peaking at 27°C (81°F). The month sees about 97 mm (3.8 in) of precipitation over roughly 10 days, with humidity around 68%. In contrast, February experiences much colder weather, with temperatures dipping to a minimum of -13°C (10°F) and averaging only 2°C (37°F), reaching a maximum of 12°C (53°F). Precipitation increases to 127 mm (5.0 in) over about 12 days, accompanied by higher humidity levels of 82%. For a more detailed look at February conditions, you can check Southampton weather in February.
In comparing the weather of September and March, one can observe significant differences in temperature and general climate. September enjoys milder temperatures, with averages around 20°C (69°F) and a maximum of 27°C (81°F), making it a pleasant month for outdoor activities. In contrast, March is much cooler, with average temperatures only reaching 4°C (39°F) and a maximum of 15°C (59°F), creating a stark transition into spring. Additionally, while both months experience around 10 days of precipitation, March has a slightly higher amount at 112 mm (4.4 in), compared to September's 97 mm (3.8 in). The humidity levels are also higher in March at 81%, compared to September's 68%, contributing to a damp chill that marks the early spring season. For a more detailed look at specific weather conditions during this time, check out Southampton weather in March.
When comparing the weather in September and April, one can see distinct differences. September typically boasts a warmer climate with average temperatures around 20°C (69°F), peaking at 27°C (81°F), while April experiences cooler conditions with an average of only 8°C (47°F) and a maximum of 17°C (63°F). Precipitation is also notable; September averages 97 mm (3.8 in) over 10 days, whereas April sees a higher total of 139 mm (5.5 in) across 12 days. Additionally, humidity levels are slightly elevated in April at 78%, compared to 68% in September. For more detailed information, you can visit Southampton weather in April.
When comparing the weather in September and May, several distinctions emerge. September typically presents milder temperatures, with a range from a minimum of 12°C (55°F) to a maximum of 27°C (81°F), averaging around 20°C (69°F). In contrast, May tends to be cooler, with temperatures ranging from 4°C (39°F) to 21°C (70°F) and an average of only 13°C (55°F). Precipitation is also notable; September experiences 97 mm (3.8 in) of rainfall over about 10 days, while May sees more precipitation at 130 mm (5.1 in) over 13 days. Despite these variations in temperature and precipitation, both months exhibit similar humidity levels, hovering around 68-69%. For a detailed look at weather specifics in May, you can check out Southampton weather in May.
When comparing the weather between September and June, we see some notable differences. September tends to be slightly warmer, with average temperatures reaching 20°C (69°F), peaking at 27°C (81°F), compared to June's average of 18°C (65°F) and a maximum of 25°C (77°F). Additionally, September experiences more rainfall, with 97 mm (3.8 in) over about 10 days, while June has a total of 72 mm (2.8 in) spread over 8 days. Humidity levels are quite similar in both months, hovering around 68-69%. For a more detailed look at June's climate, check out Southampton weather in June.
When comparing the weather in September to that of July, we see notable differences in temperature and humidity. September generally has a cooler range, with average temperatures of 20°C (69°F) compared to July's warmer average of 23°C (73°F). The maximum temperature in September reaches 27°C (81°F), slightly below July's peak of 29°C (84°F). Additionally, September is slightly more humid at 68%, versus July's 62%. Precipitation levels are comparable, with September receiving 97 mm (3.8 in) over 10 days, while July experiences a bit more rain at 105 mm (4.1 in) over 11 days. For more detailed insights on July's weather, you can check Southampton weather in July.
September generally experiences cooler temperatures compared to August, with a minimum of 12°C (55°F) and an average of 20°C (69°F), while August has a minimum of 17°C (63°F) and an average of 23°C (74°F). The maximum temperature in September reaches 27°C (81°F), slightly lower than August's 28°C (83°F). Both months have similar precipitation levels, with September receiving 97 mm (3.8 in) and August slightly more at 100 mm (3.9 in), occurring over roughly the same number of days. Additionally, September's humidity is a bit higher at 68% compared to August's 65%. For a more detailed look at August conditions, check out Southampton weather in August.
September weather in Southampton typically features milder temperatures, with a minimum of 12°C (55°F) and an average of 20°C (69°F), peaking at around 27°C (81°F). The month experiences moderate rainfall, totaling 97 mm (3.8 inches) over about 10 days, accompanied by a humidity level of 68%. In contrast, October sees a significant drop in temperatures, with minimums around 6°C (42°F) and an average of 16°C (62°F). Although the maximum temperature lowers to 25°C (77°F), October is wetter, with 159 mm (6.2 inches) of precipitation spread over 13 days and increased humidity at 74%. For more detailed information about October weather, you can check Southampton weather in October.
September and November present a striking contrast in weather conditions. In September, temperatures range from a minimum of 12°C (55°F) to a pleasant average of 20°C (69°F), peaking at 27°C (81°F). The month experiences about 97 mm (3.8 in) of precipitation over approximately 10 days, coupled with a humidity level of 68%. In contrast, November sees a notable drop in temperatures, with minimums plunging to -5°C (24°F) and an average of 10°C (50°F), while maximums reach only up to 19°C (67°F). Rainfall increases slightly to 111 mm (4.4 in) over the same number of days, and humidity rises to 82%. For more details on the specifics of November weather, you can visit Southampton weather in November.
September and December present stark contrasts in weather. September enjoys mild temperatures, ranging from a minimum of 12°C (55°F) to a pleasant average of 20°C (69°F), peaking at a maximum of 27°C (81°F). With 97 mm (3.8 in) of precipitation spread over 10 days and a humidity level of 68%, it feels relatively comfortable for outdoor activities. In contrast, December brings a sharp drop in temperatures, with minimums plummeting to -9°C (16°F), and an average temperature of just 5°C (42°F). The month sees a maximum of only 16°C (61°F) and significantly higher precipitation at 152 mm (6.0 in) across 11 days, combined with an increased humidity level of 80%. For those interested in a more detailed look at the December weather patterns, you can check Southampton weather in December.
As September unfolds in Southampton, the weather showcases a delightful transition from the warmth of summer to the crispness of autumn. With average temperatures gently mellowing around 20°C (69°F), this month offers a pleasant respite from the heat and humidity that can dominate the summer. However, be prepared for occasional rain, as September sees a moderate amount of precipitation over several days. This blend of comfortable warmth and refreshing showers makes it an ideal time for outdoor activities while the foliage begins to change. Whether you're enjoying a stroll in the park or exploring local attractions, September's weather stands apart, providing a unique charm that sets the tone for the coming seasons. For more insights into weather trends, check out Southampton Climate.