Last updated: August 21, 2025
September in Fujisawa, Japan, offers a warm and humid climate, with temperatures peaking at a comfortable 29°C (84°F) and averaging around 24°C (75°F). Visitors can expect mild evenings, with lows of 18°C (65°F) inviting pleasant outdoor experiences. However, this month also brings significant rainfall, totaling 208 mm (8.2 in) over approximately 17 days, resulting in a humidity level of 86% that adds to the lush atmosphere. Whether you're exploring coastal attractions or enjoying the vibrant local culture, September's unique weather presents a blend of warmth and refreshing rain.
In September, Fujisawa experiences a delightful transition as summer wanes and autumn approaches. The temperatures reflect this change, with a minimum of 18°C (65°F) and a comfortable average of 24°C (75°F), peaking at a warm 29°C (84°F). This month's weather is characterized by a gradual cooling compared to the sweltering heat of August, where temperatures frequently reach 31°C (87°F). The pleasant warmth in September makes it an ideal time for outdoor activities and enjoying the stunning landscapes of this coastal city, setting the stage for the crisp, refreshing days of October ahead.
In September, Fujisawa experiences a notable uptick in precipitation, with 208 mm (8.2 in) of rain falling over approximately 17 days. This marks a continuation of the month-to-month increase in rainfall leading into the autumn season, following a summer characterized by heavy downpours, especially in July, which recorded the highest levels at 226 mm (8.9 in). Comparatively, September's rainfall is among the heaviest of the year, exceeded only by the even wetter October. The frequency of rainy days also mirrors this trend, as September ties with July for the most rainfall days, indicating a pronounced shift toward the wet season. As the summer heat gives way to cooling temperatures, residents and nature alike brace for the robust arrival of autumn rains.
September in Fujisawa, Japan, marks the transition from the sweltering summer months to the milder autumn season, with humidity levels reaching 86%. This slight decline from the peak of 93% in July and 90% in August indicates a gradual easing of the muggy summer atmosphere. The trend shows a general increase in humidity from the cooler winter months, peaking in the summer, and then slowly tapering off as fall approaches. With May experiencing a notable 81%, and a significant rise during the summer, September's humidity level exemplifies the lingering warmth while hinting at the cooler, drier weather to come. As the month progresses, residents can expect a subtle shift that balances comfort and the remnants of the summer's humidity.
As September settles in Fujisawa, Japan, the UV Index remains strikingly high at 10, categorizing it as very high and indicating a burn time of just 15 minutes. This mirrors the intense summer months, where the Index consistently peaked at 11, classified as extreme. While the UV levels start to dip from the scorching summer, the risk remains significant, urging residents and visitors to take precautions against sun exposure. Historically, September sees a slowdown from the highest peaks observed in earlier summer months, yet the need for vigilance is still essential. For more detailed information on UV levels throughout the year, check out the comprehensive guide on Fujisawa UV Index.
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As summer wanes, September in Fujisawa, Japan, offers a gentle transition to autumn with a pleasing 239 hours of sunshine. This month stands out, as it follows a sun-drenched August that boasted an impressive 297 hours of bright skies. The trend throughout the year reveals an upward trajectory in sunshine hours from January to May, peaking dramatically in August before slightly dipping in September. With days still warm and sunlight embracing the city, September maintains a generous share of sunshine, bridging the summer's vibrant energy and the cooler embrace of fall. Overall, the gradual decline in sunlight from the mid-year peak pairs beautifully with the crispness of early autumn, creating a delightful atmosphere for residents and visitors alike.
As summer fades, September in Fujisawa, Japan ushers in a notable shift in weather patterns. With a sun probability of only 29%, this month tends to be less sunny compared to the preceding summer months, which hover around mid-30% ranges. The trend indicates a transition toward more cloud cover and potential rainfall, diverging from the vibrant sunshine of July and August. However, the likelihood of sunny days elevates again into the autumn months of October and November, which boast 48% and 62% chances, respectively. Thus, while September may offer fewer sun-filled days, the promise of brighter skies looms just around the corner.
In Fujisawa, Japan, September marks a gentle transition from the bright, long days of summer into the more subdued autumn months. With 12 hours of daylight, the city experiences a slight decrease from the peak of 14 hours in the summer months of June and July. This gradual shift is reflective of a larger annual trend, where daylight hours steadily increase from 10 hours in winter to a peak in late spring and summer, before tapering off again as the year moves towards winter. As September unfolds, residents enjoy slightly shorter days, signaling the approach of cozy fall evenings while still basking in the warm afterglow of summer's light.
As September dawns in Fujisawa, Japan, the wind picks up to an average speed of 5.2 m/s (12 mph), mirroring the gentle breezes of late summer. This slight uptick from August’s 5.0 m/s (11 mph) suggests a transitional phase, as the warmer months give way to cooler autumnal air. Interestingly, after a noticeable dip during the height of summer with July recording just 3.3 m/s (7 mph), winds return to more moderate levels into autumn. The overall trend indicates a comforting consistency in wind patterns, with speeds averaging between 5.2 to 5.8 m/s throughout the year, creating a delightful backdrop for the vibrant coastal life. As Fujisawa welcomes the calming winds of September, residents and visitors alike can relish the refreshing atmosphere that the onset of fall brings.
Weather in Fujisawa varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Fujisawa, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present contrasting weather patterns. In September, temperatures range from a minimum of 18°C (65°F) to a maximum of 29°C (84°F), with an average of 24°C (75°F), accompanied by high humidity levels of 86%. The month is also characterized by significant precipitation, totaling 208 mm (8.2 in) across 17 days. In stark contrast, January experiences much cooler temperatures, with a minimum of 1°C (34°F) and an average of 8°C (47°F), peaking at 18°C (64°F). January is notably drier, recording just 64 mm (2.5 in) of precipitation over 6 days, along with a lower humidity level of 76%. For a more detailed look at winter weather, visit Fujisawa weather in January.
September and February present stark contrasts in weather. September boasts warmer temperatures, with a minimum of 18°C (65°F) and an average high of 29°C (84°F), making it a comfortable month. However, it also experiences significant rainfall, with 208 mm (8.2 in) over 17 days, and a high humidity level of 86%. In contrast, February is much cooler, with temperatures ranging from a minimum of 2°C (36°F) to a maximum of 17°C (63°F), averaging only 8°C (47°F). The precipitation in February is much lighter, totaling 62 mm (2.4 in) over 8 days, accompanied by lower humidity at 74%. For more insights on February conditions in Fujisawa, check out Fujisawa weather in February.
September and March present contrasting weather patterns. In September, temperatures are noticeably warmer, with a minimum of 18°C (65°F) and an average of 24°C (75°F), reaching a maximum of 29°C (84°F). The month sees significant rainfall, totaling 208 mm (8.2 in) over about 17 days, combined with high humidity levels of 86%.
In stark contrast, March experiences much cooler temperatures, with a minimum of 3°C (38°F), an average of 11°C (52°F), and a maximum of 19°C (66°F). Although it is drier than September, March still has a fair amount of precipitation at 172 mm (6.8 in) over 12 days, but with considerably lower humidity at 70%. For more specific details on March weather, you can visit Fujisawa weather in March.
When comparing the weather in September and April, it’s evident that September is significantly warmer and more humid. September experiences average temperatures ranging from a minimum of 18°C (65°F) to a maximum of 29°C (84°F), while April has cooler averages, with temperatures ranging from 6°C (43°F) to 21°C (70°F). Additionally, September sees more precipitation, with 208 mm (8.2 in) of rain over 17 days, in contrast to April's 141 mm (5.5 in) over just 12 days. The humidity in September is also higher at 86%, compared to 74% in April, making September feel more muggy. For more details on the weather during April, you can check Fujisawa weather in April.
In comparing the weather between September and May, September tends to be warmer, with average temperatures ranging from a minimum of 18°C (65°F) to a maximum of 29°C (84°F), while May has cooler temperatures, with a range from 12°C (54°F) to 23°C (74°F). Additionally, September experiences significantly higher precipitation at 208 mm (8.2 in) over 17 days, compared to May's 148 mm (5.8 in) over just 11 days. The humidity levels are also slightly higher in September at 86%, contrasted with 81% in May. For more detailed insights on May weather specifically, refer to this link: Fujisawa weather in May.
In comparing the weather of September and June, September tends to be warmer overall. The average temperature in September reaches 24°C (75°F), with maximums of 29°C (84°F), while June has a cooler average of 21°C (70°F) and maximums of 26°C (79°F). However, September also experiences more rainfall, with 208 mm (8.2 in) over 17 days compared to June's 197 mm (7.8 in) across 13 days. Additionally, humidity levels are slightly lower in September at 86% versus 88% in June, making September feel a touch more comfortable despite the increased precipitation. For a more detailed look at June's weather, you can visit Fujisawa weather in June.
In comparing the weather of September and July, we find that September has slightly cooler temperatures, with an average of 24°C (75°F) compared to July's warmer average of 25°C (77°F). Both months experience a similar range of temperatures, with September peaking at 29°C (84°F) and July at 28°C (83°F). However, September tends to be wetter, receiving 208 mm (8.2 in) of precipitation over 17 days, while July has a higher rainfall total of 226 mm (8.9 in), also over 17 days. Humidity levels are slightly lower in September at 86%, compared to July’s 93%, making September feel a bit more comfortable overall. For a closer look at July's climate specifics, you can refer to Fujisawa weather in July.
In September, the weather is noticeably cooler than in August, with average temperatures dropping from 27°C (80°F) in August to 24°C (75°F) in September. Specifically, September sees minimum temperatures of 18°C (65°F) compared to a warmer minimum of 21°C (70°F) in August. While both months experience high humidity, September's average humidity is slightly lower at 86%, compared to August's 90%. Additionally, September receives more precipitation, totaling 208 mm (8.2 in) over 17 days, in contrast to August’s 129 mm (5.1 in) across just 12 days. For more details on weather patterns during August, you can visit Fujisawa weather in August.
September and October weather presents a noticeable shift. September boasts warmer temperatures with a minimum of 18°C (65°F), an average of 24°C (75°F), and a maximum of 29°C (84°F). However, the month sees significant rainfall, totaling 208 mm (8.2 in) over 17 days and accompanied by high humidity at 86%. In contrast, October experiences cooler temperatures, with a minimum of 13°C (56°F), an average of 20°C (68°F), and a maximum of 26°C (79°F). Precipitation increases to 303 mm (11.9 in), also spread across 17 days, while humidity slightly decreases to 83%. For a more detailed look at October's weather, check out Fujisawa weather in October.
In September, the weather is much warmer, with temperatures ranging from a minimum of 18°C (65°F) to a maximum of 29°C (84°F) and an average of 24°C (75°F). The month also sees significant rainfall, totaling 208 mm (8.2 in) over 17 days, coupled with high humidity at 86%. In contrast, November brings cooler temperatures, with a minimum of 6°C (43°F), an average of 15°C (60°F), and a maximum of 21°C (71°F). Precipitation decreases to 111 mm (4.4 in) over 12 days, and humidity drops slightly to 80%. For more details, visit Fujisawa weather in November.
September and December exhibit strikingly different weather patterns. In September, temperatures range from a minimum of 18°C (65°F) to a maximum of 29°C (84°F), with an average of 24°C (75°F). The month is characterized by high humidity at 86% and significant precipitation, totaling 208 mm (8.2 in) over 17 days. In contrast, December brings much cooler temperatures, with a minimum of 3°C (37°F) and an average of 11°C (52°F), peaking at 21°C (69°F). Rainfall is considerably less in December, amounting to 82 mm (3.2 in) over just 11 days and accompanied by lower humidity levels at 78%. For more detailed information, check out Fujisawa weather in December.
As September wraps up the summer season in Fujisawa, it brings a unique blend of warmth and humidity that sets it apart from the preceding months. With temperatures still peaking close to 29°C (84°F), it maintains a balmy feel, but an increase in precipitation, averaging 208 mm (8.2 in) over 17 days, signals the transition to autumn. The humidity rests at a high 86%, creating a lush and vibrant atmosphere, while the cooling evenings, with lows around 18°C (65°F), invite a refreshing contrast. For those planning a visit, it's an ideal time to experience Fujisawa's evolving climate and seasonal shifts. For more detailed insights on the weather patterns, check out Fujisawa Climate.