Last updated: August 21, 2025
In September, Tsukuba, Japan experiences a dynamic weather pattern characterized by a broad temperature range, with highs reaching up to 35°C (95°F) and lows dipping to 12°C (54°F). The average temperature hovers around a pleasant 23°C (74°F), making it an inviting time for outdoor activities. However, the month is also marked by significant precipitation, totaling 157 mm (6.2 in) over 17 days, making humidity levels soar to 89%. Visitors and residents alike should be prepared for the occasional rain shower while enjoying the warm and vibrant atmosphere of this early autumn month.
In September, Tsukuba experiences a delightful transition as summer begins to fade, revealing a balance between warmth and cooling breezes. With minimum temperatures hovering around 12°C (54°F) and an average of 23°C (74°F), this month invites both outdoor exploration and seasonal change. The maximum temperatures can reach up to 35°C (95°F), hinting at the lingering summer heat. As the month progresses, these warmer days gradually give way to the crispness of autumn, demonstrating a marked shift from the sweltering heights of July and August. This seasonal blend makes September an appealing time to enjoy everything from vibrant festivals to picturesque nature walks in Tsukuba.
In September, Tsukuba experiences a notable shift as the monthly precipitation peaks at 157 mm (6.2 in), a significant increase compared to the preceding months. This surge is accompanied by 17 rainy days, contributing to a sense of transition as summer gives way to autumn. Notably, this pattern continues the wetter trend established in July and August, where the rainfall combined with a higher number of precipitation days creates a dynamic and moist atmosphere. As the rainy season recedes, the October outlook suggests an even heftier rainfall average, marking September as a pivotal month in the region's climatic rhythm. This blend of rainfall and the changing seasons underscores the meteorological tapestry that defines Tsukuba's weather profile.
In September, Tsukuba, Japan experiences a notable shift in humidity levels, with an average of 89% that hints at the lingering impact of summer's heat. Following a peak in July and August at 92%, the humidity begins to ease, yet remains relatively high compared to the earlier months of the year. As the seasons transition, humidity gradually decreases from its summer highs, reflecting the onset of autumn. This seasonal fluctuation showcases how September retains a significant level of moisture, ensuring that the air remains crisp yet somewhat heavy, setting the stage for the milder months ahead.
In September, Tsukuba, Japan, witnesses a UV Index of 9, indicating a very high level of solar radiation and a burn time of just 15 minutes for unprotected skin. As summer transitions into autumn, the UV levels gradually decrease from the extreme highs of July and August, yet still remain notably potent. This trend highlights the importance of sun protection, even as the days begin to cool. The consistent presence of high to very high UV levels from April through September serves as a reminder to remain vigilant in sun safety practices. For more detailed information on UV conditions, visit Tsukuba UV Index.
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As summer fades, September in Tsukuba, Japan, brings a transition marked by its 221 hours of sunshine. While this is a dip from the sun-drenched days of August, which boasted 265 hours, it still surpasses the early months of the year. Notably, the increase in daylight from January's modest 188 hours to the peak in May reflects the region's gradual warming and the vibrancy of spring. Although September’s sunshine hours trail those of the hotter months, they remain consistent with the autumnal trend, continuing the varied tapestry of light that characterizes Tsukuba's seasons. Overall, this month serves as a gentle reminder of the shifting seasons, blending the warm remnants of summer with the crisp beginnings of fall.
In Tsukuba, Japan, September marks a transitional period as summer fades, with a 26% chance of sunny weather. This figure aligns with the trend observed during the late summer months, where sunshine also tends to be sparse. As the seasons shift, probabilities for clearer skies gradually improve, particularly heading into the more favorable months of October and November, boasting 46% and 63% chances of sun, respectively. While September may not offer the brightest days, it still holds potential for those seeking a gentle end to summer’s heat.
As summer fades, September in Tsukuba, Japan marks a gentle transition with about 12 hours of daylight, slightly less than the sunny peaks of July and August, which each bask in 14 hours. This month signals the beginning of shorter days, as nature prepares for the cooler seasons ahead. The gradual decrease in daylight from the vibrant 14 hours of late summer to 12 hours reflects the shifting patterns of the year, reminding us of the cyclical beauty of the seasons. Following September, daylight continues to dwindle, paving the way for the cozy, candle-lit evenings of autumn.
In September, the wind in Tsukuba, Japan carries a gentle calm, with an average speed of 2.4 m/s (5 mph). This marks a slight uptick from the quieter summer months, where July recorded its lowest at 1.9 m/s (4 mph), and provides a breath of fresh air as nature transitions into autumn. April and August peak at 2.9 m/s and 2.6 m/s, respectively, suggesting that spring and the late summer months are the breeziest periods in Tsukuba. As the temperature begins to cool, September’s winds serve as a reminder of the changing seasons. Overall, the wind patterns reveal a gradual ebb and flow throughout the year, with a tendency for slightly stronger breezes during the spring and early autumn.
Weather in Tsukuba varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Tsukuba, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January showcase distinctly contrasting weather patterns. In September, temperatures range from a mild minimum of 12°C (54°F) to a scorching maximum of 35°C (95°F), with an average of 23°C (74°F). The month also experiences considerable precipitation, totaling 157 mm (6.2 in) over 17 days, contributing to a high humidity level of 89%. Conversely, January presents a chilly climate, with temperatures dipping as low as -10°C (14°F) and peaking at 17°C (63°F), averaging just 4°C (39°F). This month sees significantly less rainfall, with 38 mm (1.5 in) over only 4 days, while humidity remains similar at 88%. For more detailed weather insights, check out Tsukuba weather in January.
September and February present markedly different weather experiences. In September, temperatures range from a minimum of 12°C (54°F) to a maximum of 35°C (95°F), with an average of 23°C (74°F), creating a warm and often humid atmosphere with 89% humidity. This month also sees significant rainfall, totaling 157 mm (6.2 in) over approximately 17 days. In contrast, February features much cooler temperatures, with a minimum of -5°C (23°F) and a maximum of 21°C (70°F), averaging just 5°C (42°F). The precipitation is much lighter at 37 mm (1.5 in) spread over about 6 days, and humidity remains slightly lower at 86%. For more detailed insights on February's weather, you can check Tsukuba weather in February.
In September, the weather tends to be significantly warmer with average temperatures around 23°C (74°F) and maximums reaching up to 35°C (95°F), presenting a stark contrast to March, where the average temperature drops to 9°C (49°F) and minimums can be as low as -4°C (25°F). September also experiences higher humidity levels at 89%, compared to March’s relatively drier 81%. Additionally, September sees more precipitation, with 157 mm (6.2 in) over approximately 17 days, while March has 124 mm (4.9 in) of rainfall across 11 days. For more detailed insights about the weather in March, you can check Tsukuba weather in March.
September weather contrasts significantly with that of April. In September, temperatures range from a mild 12°C (54°F) at night to a scorching 35°C (95°F) during the day, with an average of 23°C (74°F). The month is characterized by high humidity at 89% and significant precipitation, totaling 157 mm (6.2 in) over 17 days. In contrast, April experiences much cooler conditions, with nighttime lows dipping to -1°C (31°F) and daytime highs reaching 29°C (84°F), leading to a more comfortable average temperature of 14°C (57°F). This month has lower rainfall, with 112 mm (4.4 in) spread across 11 days, and a humidity level of 78%. For more detailed information on April weather, you can visit Tsukuba weather in April.
September and May present contrasting weather patterns, particularly in temperature and humidity. In September, the average temperature reaches a warm 23°C (74°F), with a significant maximum of 35°C (95°F) and a high humidity of 89%, which can make the air feel quite muggy. This month also sees more rainfall, with 157 mm (6.2 in) of precipitation over 17 days. In contrast, May’s weather is milder, featuring an average temperature of 19°C (67°F) and a maximum of 34°C (93°F) but with lower humidity at 81%. Rainfall in May is also less, totaling 123 mm (4.8 in) over 12 days. For more detailed information, you can check Tsukuba weather in May.
September weather in Tsukuba features a warmer average temperature of 23°C (74°F) compared to June's average of 22°C (72°F). While both months have similar minimum temperatures, September can reach higher peak temperatures, with a maximum of 35°C (95°F), compared to June's maximum of 33°C (92°F). Additionally, September experiences more precipitation, totaling 157 mm (6.2 in) over 17 days, while June sees slightly less at 132 mm (5.2 in) across 16 days. Humidity remains quite high in both months, with September at 89% and June at 88%. For more details, you can check out this link: Tsukuba weather in June.
When comparing the weather in September and July, September tends to be slightly cooler, with average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 35°C (95°F), while July experiences warmer temperatures, averaging between 17°C (63°F) and 37°C (98°F). In terms of precipitation, July is wetter, with 218 mm (8.6 in) of rain occurring over 20 days, compared to September's 157 mm (6.2 in) over 17 days. Additionally, humidity levels remain high in both months, with July at 92% and September at 89%. For more details on July weather, you can visit Tsukuba weather in July.
Comparing the weather in September and August reveals some notable differences. September experiences a range of temperatures with a minimum of 12°C (54°F), an average of 23°C (74°F), and a maximum of 35°C (95°F), making it generally cooler than August, which has a minimum of 17°C (62°F), an average of 28°C (82°F), and peaks at 37°C (98°F). Additionally, September sees more precipitation, with 157 mm (6.2 in) falling over 17 days, compared to August's 114 mm (4.5 in) over 14 days. Humidity levels remain high in both months, with September slightly lower at 89% compared to August's 92%. For a more detailed look at August weather patterns, visit Tsukuba weather in August.
September and October display notable differences in weather patterns. September sees warmer temperatures with a minimum of 12°C (54°F) and an average of 23°C (74°F), peaking at a maximum of 35°C (95°F). The month also experiences substantial rainfall, with a total of 157 mm (6.2 in) spread over 17 days, along with a high humidity of 89%. In contrast, October brings cooler conditions, marked by a minimum temperature of 6°C (42°F) and an average of 18°C (64°F), with a maximum reaching 32°C (90°F). Although October has slightly fewer rainy days at 14, the precipitation increases to 225 mm (8.8 in) and the humidity remains high at 87%. For further details on October's climate, you can check Tsukuba weather in October.
September and November present stark contrasts in weather conditions. In September, temperatures range from a minimum of 12°C (54°F) to a maximum of 35°C (95°F), with an average of 23°C (74°F). The month is quite humid at 89% and experiences significant rainfall, totaling 157 mm (6.2 in) over 17 days. In contrast, November sees a notable drop in temperatures, with minimums reaching -2°C (30°F) and a maximum of 23°C (74°F), averaging 12°C (54°F). Precipitation decreases to 63 mm (2.5 in) spread over just 7 days, and humidity is slightly lower at 85%. For more insights on the weather specifics for this month, refer to Tsukuba weather in November.
September and December exhibit stark contrasts in weather conditions. In September, temperatures range from a minimum of 12°C (54°F) to a scorching maximum of 35°C (95°F), with an average of 23°C (74°F). The month is marked by high humidity at 89% and significant precipitation, totaling 157 mm (6.2 in) over 17 days. In contrast, December brings much colder temperatures, with lows plunging to -4°C (26°F) and an average of only 6°C (43°F), peaking at 20°C (68°F). The precipitation drops notably to 50 mm (1.9 in) across just 6 days, and humidity remains relatively stable at 86%. For more detailed information about December weather in this region, visit Tsukuba weather in December.
As September rolls in, Tsukuba experiences a distinct transition in weather, characterized by high humidity and considerable rainfall. This month marks a departure from the summer heat, cooling down with average temperatures that provide much-needed relief. However, the increased precipitation, coupled with a higher number of rainy days, sets September apart from the drier summer months. As the city prepares for the onset of autumn, the lush greenery flourishes under the damp conditions, creating a vibrant landscape. For a deeper dive into Tsukuba's climate trends, explore our detailed section on Tsukuba Climate.