Last updated: February 6, 2025
September in San Sebastian reveals a delightful blend of warmth and occasional showers, with maximum temperatures reaching a pleasant 29°C (85°F) and an average hovering around 18°C (65°F). The month can see minimums dipping to 9°C (48°F), creating a comfortable atmosphere for both locals and visitors. Despite experiencing 12 days of rainfall totaling 97 mm (3.8 in), the city's humidity remains a notable 75%, enhancing the lush landscapes and vibrant scenery. Whether soaking up the sun or enjoying a refreshing drizzle, September showcases the unique charm of this coastal gem.
In September, San Sebastian experiences a delightful transition as summer gracefully gives way to autumn. With minimum temperatures around 9°C (48°F) and a pleasant average of 18°C (65°F), the city enjoys a comfortable climate. The maximum temperatures can soar to a warm 29°C (85°F), enticing locals and visitors alike to revel in outdoor activities and stunning coastal views. This month marks a notable drop from the peak summer warmth of August, yet it remains pleasantly mild, making it an ideal time for exploring the vibrant local culture, indulging in delicious pintxos, or unwinding on the picturesque beaches. As September rolls in, the enchanting blend of warmth and gentle breezes create a perfect backdrop for unforgettable experiences in this Basque gem.
In September, San Sebastián experiences a transition as summer fades, bringing with it 97 mm (3.8 in) of rainfall over approximately 12 days. This marks a slight increase from the drier months of July and August, where precipitation was relatively low at 93 mm and 95 mm, respectively. As the city moves into autumn, the frequency of rain begins to rise, setting the stage for a wetter October and November. The shifting weather patterns showcase San Sebastián's climate; while September tends to remain mild, it hints at the impending increase in precipitation that characterizes the later months of the year.
As autumn approaches, September in San Sebastián welcomes a noticeable dip in humidity, averaging 75%, the lowest of the year. This decline marks a shift from the summer months, where humidity levels comfortably hover around the mid-70s. Following a peak in January at 86%, humidity gradually decreases until the summer's end, while October sees a rebound to 81%. This cyclical trend highlights the region's maritime climate, where the cooler September air provides a refreshing contrast to the humidity-laden heat of summer, making it an ideal time for outdoor exploration in this scenic coastal town.
As September rolls into San Sebastián, the UV Index begins to decrease from the summer peak, settling at a high level of 7. This shift marks a transition from the intense summer sun, where levels reached a very high 10, to more moderate conditions, but caution is still advised. With a burn time of just 25 minutes, it's essential to protect your skin during outdoor activities, even as the days grow slightly shorter. The trend reflects a gradual easing into autumn, with UV exposure remaining significant compared to the earlier months of the year, so staying sun-smart is vital. For more detailed information on UV levels throughout the year, check out San Sebastian UV Index.
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September in San Sebastián is a delightful transition into autumn, boasting 335 hours of sunshine that enhances the city's picturesque beauty. As summer unwinds, it's fascinating to observe a slight dip from the peak solar glory of July's 403 hours. This trend reflects a gradual decrease in daylight, yet September still holds onto the warmth and charm of summer days. The sun-drenched beaches and vibrant local culture remain inviting, making it an ideal time for visitors to explore. Notably, the sunlight persists well into the month, providing a stunning backdrop for leisurely strolls along the coastal promenade or savoring the rich culinary offerings of this Basque gem.
In San Sebastian, Spain, the likelihood of encountering sunny weather in September stands at 28%, reflecting a slight dip compared to the sunnier summer months of July and August, which boast chances of 34% and 37%, respectively. This trend illustrates the gradual transition from summer's warmth to autumn's cooler embrace, as the chance of sunshine decreases significantly going into the latter part of the year. Notably, the percentage of sunny days in September is on par with the cloudy tendencies seen in May and June, marking the tail end of the more favorable sun-drenched season. As we look towards the months ahead, the chances of clear skies begin their seasonal decline, with November's percentage sinking to 17%, emphasizing the tempting opportunity that September still holds for those seeking a glimpse of sun before the rainier days set in.
In San Sebastián, Spain, the daylight duration experiences a gradual ebb and flow throughout the year, with September marking a noticeable transition. After basking in long, sun-soaked days peaking at 15 hours in June, the hours of daylight begin to wane. By September, residents and visitors enjoy about 12 hours of daylight, providing a perfect blend of light for outdoor activities while hinting at the upcoming fall. As the month progresses, this trend continues, leading into October's shorter days with only 10 hours of daylight. This cyclical pattern not only reflects the seasonal changes but also resonates with the vibrant rhythm of life in this coastal city, where each hour of sunlight is cherished as summer's warmth begins to recede.
As summer fades and September arrives in San Sebastián, the coastal winds begin to show subtle shifts, reflecting the transition into autumn. With an average wind speed of 2.7 m/s (6 mph), September marks a slight uptick from the calmest summer months, yet it still maintains the gentle breeziness characteristic of this vibrant coastal town. This gentle wind provides a refreshing contrast to the warmer days while hinting at the stronger gusts of October that follow. Overall, this month serves as a delicate bridge between the bustling energy of summer and the crisp rejuvenation of fall, inviting both locals and visitors to enjoy the mesmerizing coastal scenery in a comfortable atmosphere.
The weather in San Sebastian 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 San Sebastian and find detailed weather information for every month.
September and January present quite contrasting weather patterns. In September, temperatures range from a mild 9°C (48°F) to a warm 29°C (85°F), with an average of 18°C (65°F). This month experiences lower humidity levels at 75% and a total precipitation of 97 mm (3.8 in) over 12 rainy days. In stark contrast, January sees temperatures drop significantly, with lows of -2°C (29°F) and highs reaching only 18°C (65°F), marking an average temperature of 7°C (45°F). Additionally, January is wetter, with 147 mm (5.8 in) of rain over 14 days and higher humidity at 86%. For more detailed insights into January weather, check out San Sebastian weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a mild 9°C (48°F) at night to a warm 29°C (85°F) during the day, with an average of 18°C (65°F). The month experiences around 97 mm (3.8 in) of rainfall over approximately 12 days, accompanied by a humidity level of 75%, creating a somewhat comfortable atmosphere. In stark contrast, February is much cooler, with temperatures dipping as low as -4°C (25°F) at night and reaching a maximum of 22°C (71°F), averaging 9°C (49°F). Rainfall is slightly higher at 130 mm (5.1 in) over 13 days, and the humidity increases to 85%, contributing to a chillier feel. For a deeper dive into February's climate specifics, check out San Sebastian weather in February.
September and March present quite distinct weather profiles. In September, temperatures range from a mild 9°C (48°F) at night to a warm 29°C (85°F) during the day, with an average of 18°C (65°F). The month sees a fair amount of precipitation, totaling 97 mm (3.8 in) over about 12 days, accompanied by a comfortable humidity level of 75%. In contrast, March experiences a broader temperature range, with minimums dipping to -1°C (30°F) and a maximum of 22°C (71°F), averaging around 10°C (51°F). This month is also wetter, recording 124 mm (4.9 in) of rain distributed over approximately 17 days, while humidity levels rise to 82%. This makes March feel much cooler and damper, highlighting the transition from winter to spring. For more detailed information, you can check out San Sebastian weather in March.
September and April showcase contrasting weather patterns. In September, temperatures range from a minimum of 9°C (48°F) to a comfortable average of 18°C (65°F), peaking at 29°C (85°F). The month experiences significant rainfall with 97 mm (3.8 in) spread over 12 days and an average humidity of 75%. In contrast, April is cooler, with temperatures dipping to a minimum of 1°C (34°F), averaging 12°C (54°F), and reaching a maximum of 23°C (74°F). Although it has slightly more rainfall at 108 mm (4.3 in) over 14 days, the humidity is higher at 81%. For a detailed look at April weather, visit San Sebastian weather in April.
In September, temperatures generally range from a minimum of 9°C (48°F) to a maximum of 29°C (85°F), with an average of 18°C (65°F). The month sees about 97 mm (3.8 in) of precipitation over roughly 12 days, accompanied by a humidity level of 75%. In contrast, May experiences slightly cooler conditions, with temperatures ranging from 4°C (39°F) to 27°C (80°F), averaging at 14°C (58°F). While May has a higher total precipitation of 120 mm (4.7 in) spread over 17 days, it also presents a marginally higher humidity at 80%. For more detailed insights, you can check out San Sebastian weather in May.
In comparing the weather of September and June, we observe that both months offer mild temperatures, with September experiencing a range from a minimum of 9°C (48°F) to a maximum of 29°C (85°F), while June shows slightly higher temperatures, with a minimum of 10°C (50°F) and a maximum of 32°C (90°F). Interestingly, June tends to be wetter, with 135 mm (5.3 in) of precipitation over 15 days compared to September's 97 mm (3.8 in) over 12 days. Additionally, June's average humidity is slightly higher at 81% compared to September's 75%. For more detailed insights into June weather, you can refer to San Sebastian weather in June.
When comparing the weather in September and July, notable differences emerge in temperature and humidity. September experiences cooler temperatures, with a minimum of 9°C (48°F) and a maximum of 29°C (85°F), while July is warmer, with a minimum of 12°C (53°F) and a maximum of 33°C (91°F). Both months see similar levels of precipitation, with September receiving 97 mm (3.8 in) over 12 days and July slightly less at 93 mm (3.7 in) over 14 days. Additionally, humidity is marginally higher in July at 80%, compared to September's 75%. For more details on the July climate, visit San Sebastian weather in July.
In comparing the weather between September and August, we see a notable shift in temperature and precipitation patterns. September experiences cooler temperatures, with average highs of 29°C (85°F) compared to August's 31°C (88°F). The minimum temperatures also drop, with September starting at 9°C (48°F), in contrast to August's 12°C (53°F). Precipitation levels remain similar, with September seeing 97 mm (3.8 in) over 12 days, while August has slightly less at 95 mm (3.7 in) over 15 days. Humidity levels are comparable, with September at 75% and August a touch higher at 76%. For more details on the conditions in August, you can visit San Sebastian weather in August.
In September, the weather is generally warmer, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 29°C (85°F) and an average of 18°C (65°F). The month experiences 97 mm (3.8 in) of precipitation over 12 days, along with a humidity level of 75%. In contrast, October brings cooler temperatures, with a minimum of 5°C (41°F), an average of 15°C (59°F), and a maximum of 26°C (79°F). Precipitation increases to 135 mm (5.3 in) spread over 14 days, along with slightly higher humidity at 81%. For more detailed information about October weather, visit San Sebastian weather in October.
September and November present contrasting weather patterns, with September enjoying warmer temperatures and lower precipitation. In September, the temperature ranges from a minimum of 9°C (48°F) to a maximum of 29°C (85°F), averaging around 18°C (65°F). The month typically sees about 97 mm (3.8 in) of rainfall over 12 days, with humidity at 75%. In contrast, November brings cooler temperatures, with a minimum of 2°C (36°F) and a maximum of 22°C (72°F), averaging just 11°C (52°F). This month is also wetter, receiving 190 mm (7.5 in) of rain over 18 days and experiencing higher humidity at 85%. For more detailed insights, you can check San Sebastian weather in November.
September and December exhibit markedly different weather patterns. In September, temperatures range from a minimum of 9°C (48°F) to a maximum of 29°C (85°F), with an average of 18°C (65°F). The month experiences relatively moderate precipitation of 97 mm (3.8 in) over 12 days, along with a humidity level of 75%. In contrast, December brings cooler temperatures with a minimum of -1°C (31°F), an average of 9°C (49°F), and a maximum of 18°C (64°F). This month sees a significant increase in precipitation, totaling 217 mm (8.5 in) across 17 days, alongside higher humidity at 87%. For a more detailed look at the weather conditions during this time, you can visit San Sebastian weather in December.
As September graces San Sebastian, it offers a delightful transition from the summer's warmth to the inviting embrace of autumn. With maximum temperatures reaching a pleasant 29°C and an average of 18°C, this month is a perfect time for outdoor activities before the cooler days set in. However, expect a fair share of precipitation, with around 12 days experiencing light rain, contributing to the lush greenery the region is known for. The humidity level remains relatively high at 75%, adding a touch of moisture that enhances the charm of this coastal city. For a deeper dive into the yearly weather patterns, explore the San Sebastian Climate.