Last updated: August 21, 2025
In September, Hamamatsu, Japan experiences a dynamic climate marked by significant temperature fluctuations and notable humidity levels. With a maximum temperature soaring to 36°C (96°F) and an average settling around 25°C (77°F), the month showcases warm days, while the minimum can drop to a cooler 15°C (60°F) at night. This transitional period also brings substantial precipitation, totaling 222 mm (8.7 in) over approximately 20 days, resulting in a high humidity of 86%. Such conditions create a lush environment, making it a unique time to witness the vibrant changes in nature and culture that typify this region.
As summer transitions to autumn in Hamamatsu, Japan, September brings a refreshing change with temperatures ranging from a minimum of 15°C (60°F) to a maximum of 36°C (96°F). The average temperature of 25°C (77°F) indicates a comfortable warmth, perfect for enjoying outdoor activities before the cooler months arrive. Notably, while September retains some of the lingering heat from August, it marks a downward trend in maximum temperatures as the region prepares for the crispness of October. The gradual decline in nighttime lows also hints at the approaching fall season, making this month a delightful bridge between the sweltering summer and the cooler autumn days ahead.
September in Hamamatsu, Japan, sees a substantial 222 mm (8.7 in) of rainfall, marking a continuation of the region's wet season. With precipitation recorded over 20 days, it follows the heavy downpours of July and the relatively drier August, showcasing a seasonal peak in moisture. This trend illustrates Hamamatsu's transition from the sweltering summer months to the refreshing autumn, as September ranks among the wettest months of the year. Notably, the escalating rainfall from June through September builds a vibrant landscape, making the region lush and green as it prepares for the cooler months ahead.
September in Hamamatsu, Japan, sees humidity levels at a comfortable 86%, marking a subtle decline from the sweltering heights of summer. As the summer months progress from July's 93% and August's 90%, this decrease hints at the shifting seasons, bringing a reprieve from the oppressive heat. The year starts with humidity hovering around 76% in January, but as spring arrives, levels dip briefly before peaking again in the warmer months. Notably, May's 81% sets the stage for the summer spike, while autumn approaches with October's 83%. This trend underscores Hamamatsu's distinct seasonal rhythms, balancing humid conditions that fluctuate dramatically throughout the year.
As September arrives in Hamamatsu, Japan, the UV Index reflects a transitional change towards milder weather, with a value of 10 that falls into the very high exposure category. This indicates a slight decrease from the summer's peak, where July recorded a blistering 12 under extreme conditions. Interestingly, September's burn time increases to 15 minutes, suggesting a brief reprieve from the intense summer sun. The trend from spring to autumn clearly shows a gradual uptick in UV levels, culminating in a noteworthy peak during the summer months. As the weather begins to cool, residents and visitors should remain mindful of sun exposure, especially as they enjoy the lingering warmth of early autumn. For more detailed information, check out the Hamamatsu UV Index.
UV Risk Categories
September in Hamamatsu, Japan, unfolds with a generous 257 hours of sunshine, continuing the vibrant summer glow that peaked in August with an impressive 317 hours. This month marks a subtle transition, as daylight begins to wane, yet the warmth remains palpable. Following a steady ascent from the depths of winter, where January only managed 189 hours, September retains a bright spirit amidst the gradual decline leading into autumn. With a luminous 299 hours in May signaling the onset of longer days, the sunshine trend showcases a gradual decrease, but still presents a delightful backdrop for outdoor festivities and enjoying the lingering warmth of summer before the October cool rolls in.
In September, Hamamatsu, Japan experiences a 30% chance of sunny weather, a figure that aligns with the trend of declining sunshine as summer transitions into autumn. While early winter months showcase a resurgence in sunny days with October boasting a 53% chance and November escalating to 62%, September remains a period of uncertainty in terms of clear skies. The summer months reflect a gradual diminishing of sunshine, with July and August hovering around the 30-34% mark before the shift into the more promising fall months. Thus, while September may not offer the most reliable weather, it sets the stage for the brighter days just around the corner.
In Hamamatsu, Japan, the transition into September marks a gentle ebb in daylight as summer gives way to autumn. With 12 hours of daylight, this month showcases a balanced blend of lingering warmth and the early whispers of cooler days ahead. The longer days of June and July, peaking at 14 hours, gradually taper off, while September enjoys a brief pause before the sun retreats further in October, bringing just 11 hours of light. This pattern reflects a natural rhythm, with daylight durations steadily decreasing from the high of summer, yet September still maintains a generous amount of sunshine, inviting residents and visitors to savor the last traces of summer's glow.
As the warmth of summer transitions to the cool embrace of autumn, September in Hamamatsu, Japan experiences a gentle breeze with an average wind speed of 2.9 m/s (7 mph). This slight decline from the summer months reflects a broader trend: the winds in Hamamatsu tend to be at their calmest during the mid-year, notably in June and July, where they drop to around 2.6 m/s (6 mph). However, as the season progresses, wind speeds gradually pick up, particularly in the months leading to winter. While September's winds are subdued, they serve as a precursor to the more dynamic flow of air that characterizes the fall transition, reminding locals of the refreshing change that autumn brings.
Weather in Hamamatsu varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Hamamatsu, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January showcase strikingly different weather patterns. In September, temperatures soar with a minimum of 15°C (60°F) and an average peak of 25°C (77°F), occasionally reaching as high as 36°C (96°F). The month is characterized by high humidity at 86% and considerable rainfall, accumulating 222 mm (8.7 in) over approximately 20 days. In contrast, January brings a chill, with temperatures dipping to a minimum of -2°C (29°F) and averaging just 7°C (44°F), peaking at 18°C (64°F). Rainfall is much lighter in January, totaling 51 mm (2.0 in) over only 4 days, and humidity decreases to 76%. For more details on January weather specifically, check out Hamamatsu weather in January.
September and February offer contrasting weather experiences. In September, temperatures range from a minimum of 15°C (60°F) to a scorching maximum of 36°C (96°F), coupled with high humidity at 86%. This month also sees significant rainfall, with precipitation reaching 222 mm (8.7 in) over approximately 20 days. In contrast, February presents a cooler climate, with temperatures dipping to a minimum of -2°C (29°F) and averaging around 7°C (46°F), peaking at a comfortable 21°C (71°F). Rainfall is much lighter in February, totaling 76 mm (3.0 in) over just 6 days, and humidity levels are relatively lower at 74%. For more details on February weather in this region, you can refer to Hamamatsu weather in February.
The weather in September and March presents a stark contrast in both temperature and precipitation. In September, temperatures range significantly from a mild 15°C (60°F) at night to a sweltering 36°C (96°F) during the day, with high humidity at 86%. This month also sees considerable rainfall, averaging 222 mm (8.7 in) over 20 days. In contrast, March offers a much cooler climate, where nighttime lows drop to around 1°C (34°F) and daytime highs peak at a comfortable 25°C (77°F). Rainfall is lighter in March, totaling 166 mm (6.5 in) over just 10 days, and the humidity level is lower at 70%. For more details on the weather in March, you can check Hamamatsu weather in March.
September and April present contrasting weather patterns, reflecting the transition from summer to autumn and from winter to spring, respectively. In September, temperatures range from a minimum of 15°C (60°F) to a sweltering maximum of 36°C (96°F), with an average of 25°C (77°F). The month is characterized by high humidity at 86% and frequent rainfall, averaging 222 mm (8.7 in) over 20 days. In stark contrast, April's weather is much cooler, with temperatures starting at a low of 3°C (37°F) and peaking at a maximum of 28°C (83°F), averaging just 15°C (60°F). April sees less precipitation, totaling 172 mm (6.8 in) over 11 days, and lower humidity at 74%. For more details on April's weather, visit Hamamatsu weather in April.
September and May present distinct weather patterns. In September, temperatures range from a minimum of 15°C (60°F) to a scorching maximum of 36°C (96°F), averaging around 25°C (77°F). This month is marked by significant precipitation, totaling 222 mm (8.7 in) across approximately 20 days, alongside high humidity levels of 86%. In contrast, May offers milder conditions with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 32°C (90°F), and an average of 20°C (68°F). Precipitation is slightly lower at 198 mm (7.8 in) over about 12 days and humidity is also a bit lesser at 81%. For more detailed information, you can check Hamamatsu weather in May.
In comparing the weather of September and June, both months have similar minimum temperatures around 15°C (59°F to 60°F), but September tends to be warmer with an average temperature of 25°C (77°F) compared to June's 23°C (74°F). The maximum temperatures also reflect this trend, with September reaching up to 36°C (96°F) while June peaks at 32°C (90°F). However, September sees less precipitation than June, with 222 mm (8.7 in) over 20 days compared to June's 261 mm (10.3 in) over 16 days. Humidity levels remain high in both months, with September at 86% and June slightly higher at 88%. For more detailed information on June weather, you can check Hamamatsu weather in June.
When comparing the weather in September and July, September generally offers slightly cooler temperatures, with a minimum of 15°C (60°F) and an average temperature of 25°C (77°F), compared to July's minimum of 19°C (67°F) and an average of 27°C (81°F). July tends to be hotter, reaching maximum temperatures of up to 40°C (105°F), while September peaks at 36°C (96°F). Precipitation is significantly higher in July, totaling 408 mm (16.1 in) across 21 days versus September's 222 mm (8.7 in) over 20 days. Additionally, humidity levels are higher in July at 93%, compared to 86% in September. For more detailed information, you can visit Hamamatsu weather in July.
September weather offers a more moderate temperature range compared to August, with minimums of 15°C (60°F) and maximums of 36°C (96°F), while August experiences higher temperatures, ranging from a minimum of 20°C (68°F) to a maximum of 42°C (107°F). Although both months see significant precipitation, September has a slightly higher total with 222 mm (8.7 in) over 20 days, compared to August's 197 mm (7.8 in) over 15 days. Humidity remains high in both months, at 86% in September and 90% in August, indicating a consistently muggy atmosphere. For a closer look at August weather specifics, you can check Hamamatsu weather in August.
September's weather is characterized by warmer temperatures, with average highs reaching 36°C (96°F) and a high level of humidity at 86%. The month also sees considerable rainfall, totaling 222 mm (8.7 inches) over 20 days. In contrast, October experiences cooler temperatures, with an average high of 32°C (89°F) and a drop in the minimum temperature to 10°C (50°F). While October has more precipitation at 293 mm (11.5 inches), it spreads over just 15 days, resulting in slightly lower humidity at 83%. For more specific details, you can check Hamamatsu weather in October.
September and November exhibit stark contrasts in weather patterns. In September, temperatures range from a minimum of 15°C (60°F) to a scorching maximum of 36°C (96°F), with an average of 25°C (77°F). The month is notably wet, receiving 222 mm (8.7 in) of precipitation over 20 days, and the humidity is a high 86%. In contrast, November sees much cooler temperatures, with a minimum of 3°C (38°F) and a maximum of 24°C (75°F), averaging 15°C (58°F). Precipitation drops significantly to 83 mm (3.3 in) over just 8 days, and humidity decreases slightly to 80%. For more detailed insights, you can check the Hamamatsu weather in November.
In September, the weather is significantly warmer, with temperatures ranging from a minimum of 15°C (60°F) to a scorching maximum of 36°C (96°F), accompanied by high humidity at 86% and substantial rainfall totaling 222 mm (8.7 in) over about 20 days. In contrast, December experiences much cooler conditions, with temperatures dropping to a minimum of 0°C (32°F) and maxing out at 23°C (74°F), along with a notable decrease in precipitation to 67 mm (2.6 in) over just 6 rainy days and slightly lower humidity at 78%. The stark difference in temperature and humidity between these two months highlights the shift from late summer warmth to the chill of early winter. For more detailed insights, check out Hamamatsu weather in December.
As September unfolds in Hamamatsu, the weather takes on a distinctive character, transitioning from the sweltering summer heat to more moderate conditions. Although temperatures can soar to a maximum of 36°C (96°F), the average drops to a more comfortable 25°C (77°F), offering a reprieve from the peak summer months. The increase in humidity, reaching a notable 86%, coupled with frequent precipitation—often totaling 222 mm (8.7 in) over about 20 days—brings a refreshing change, making the landscape lush and vibrant. This month's unique blend of warmth and moisture sets it apart, making it a transitional period where the remnants of summer slowly yield to the upcoming autumn. For a more comprehensive understanding of the region's climate nuances, visit Hamamatsu Climate.