Last updated: August 21, 2025
In September, Yamagata, Japan experiences a colorful transition into autumn with a maximum temperature reaching 35°C (95°F) and a comfortable average of 23°C (74°F). The days are warm, but the nights cool off to a minimum of 12°C (54°F), offering a refreshing contrast. This month is also marked by significant precipitation, accumulating around 298 mm (11.7 in) over 16 days, contributing to the lush landscapes of the region. The high humidity at 87% adds a tropical feel to the air, making it a unique time to experience the blend of summer’s warmth and the impending autumn chill.
In September, Yamagata, Japan, experiences a refreshing transition as summer gives way to early autumn. With nighttime temperatures averaging a mild 12°C (54°F) and daytime highs reaching a warm 35°C (95°F), the month strikes a balance that invites outdoor exploration. This warm period is complemented by a pleasant average temperature of 23°C (74°F), making it ideal for enjoying the vibrant autumn foliage that begins to emerge. As the month progresses, the summer heat gradually recedes, hinting at the cooler days to come, while maintaining a comfortable warmth that allows residents and visitors alike to savor the beauty of Yamagata's picturesque landscapes before winter sets in.
In September, Yamagata, Japan, experiences a substantial precipitation total of 298 mm (11.7 in), marking a slight decrease from the intense rains of July and August, which saw 493 mm and 322 mm, respectively. This month typically features 16 rainy days, a moderate frequency that contributes to the region's lush landscapes. The trend of increasing precipitation from January through July peaks in July before gradually tapering off as summer transitions into autumn. September’s rainfall, although still significant, signals the onset of drier months ahead, setting the stage for October's precipitation drop to 234 mm. This pattern highlights a seasonal rhythm that presents both challenges and beauty in Yamagata's climate.
In September, Yamagata, Japan experiences a humidity level of 87%, marking a slight decrease from the sweltering heights of 93% in July and 91% in August. This transition reflects the gradual shift from summer's oppressive warmth to autumn's cooler embrace. Compared to earlier months, such as June with 87% humidity and April with a lower 76%, September maintains a balance that hints at the lingering warmth while also welcoming the crispness of fall. The humidity remains relatively high as the region prepares for the changes ahead, blending a farewell to summer's heat with the freshness of the upcoming autumnal season.
In September, Yamagata, Japan experiences a UV Index that stands at a significant 10, categorizing it as very high and resulting in a burn time of just 15 minutes. This marks a slight decrease from the peak summer months, where the UV Index consistently reached 11 during June through August, deemed extreme. As autumn approaches, the UV levels begin to ease, but outdoor enthusiasts should remain vigilant. The trend from January to September showcases a pattern of increasing UV intensity from moderate levels in the winter months to extreme in the height of summer, before gently tapering off again. For more detailed information on UV exposure in Yamagata, check out Yamagata UV Index.
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As the warm embrace of September settles over Yamagata, Japan, residents and visitors alike bask in an impressive 247 hours of sunshine. This month marks a gentle transition from the radiant heat of August, which boasts the highest sunshine hours at 300, to the more tempered rays of October with 239 hours. The trend showcases a gradual decline in daylight as autumn approaches, yet September still holds its own with abundant sunlight, surpassing the earlier months of the year, such as July and June. With its comfortable temperatures and lingering daylight, September offers a perfect backdrop for enjoying the stunning fall foliage, making it a splendid time to explore the beauty of Yamagata.
As September unfolds in Yamagata, Japan, the likelihood of sunny weather stands at 29%, reflecting a generally overcast transition from summer to autumn. This marks an increase from the waning sunny days of August, which saw only 26% chance, yet still falls short of the clearer skies typical of October and November, where the probabilities jump to 58% and 59% respectively. The trend shows that while September has its share of sunshine, the region's weather is beginning to shift towards the crisp, clear days of fall. Visitors can expect a mix of sunshine tempered by the encroaching cloud cover, making it an intriguing time to explore the vibrant autumn landscape.
In Yamagata, Japan, the rhythm of daylight unfolds beautifully throughout the year. As winter yields to spring, daylight duration gradually increases, peaking in the height of summer with 14 hours of sunlight from June to August. This generous bounty of daylight begins to wane in September, offering a comforting 12 hours of sunlit skies. As autumn sets in, daylight hours continue to decline, transitioning to 11 hours in October and further to 10 hours by November. This gradual ebb and flow highlights the region's seasonal shifts, inviting residents and visitors alike to embrace the changing light as it dances across the landscape from one month to the next.
In Yamagata, Japan, the month of September typically ushers in a gentle breeze, with an average wind speed of 1.6 m/s (4 mph), making it one of the calmest months of the year. This drop in wind speed follows the summer months, which often display higher velocities, peaking at 2.4 m/s (5 mph) in May and 2.3 m/s (5 mph) in August. The transition into autumn sees a noticeable decrease, as the winds shift from the warmer, more active summer months to the cool embrace of fall. As we move into October, the winds pick up slightly again, reminding us of the dynamic climate Yamagata experiences throughout the year. This subtle ebb and flow of wind speed not only shapes the local weather patterns but also enhances the serene beauty of the region during this time.
Weather in Yamagata varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Yamagata, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present strikingly contrasting weather conditions. In September, temperatures range from a mild 12°C (54°F) to a scorching 35°C (95°F), with an average temperature of 23°C (74°F). This month sees significant rainfall, with 298 mm (11.7 in) of precipitation over approximately 16 days, contributing to a high humidity level of 87%. In stark contrast, January experiences much colder temperatures, with a minimum of -8°C (18°F) and a maximum of 16°C (60°F), averaging just 4°C (39°F). Precipitation drops significantly to 71 mm (2.8 in) across about 11 days, accompanied by a lower humidity level of 82%. For a more detailed look at the winter conditions, check out Yamagata weather in January.
September weather exhibits a warm climate with temperatures ranging from a low of 12°C (54°F) to a high of 35°C (95°F), culminating in an average of 23°C (74°F). The month is characterized by high humidity at 87% and significant precipitation, receiving around 298 mm (11.7 in) over 16 days. In contrast, February brings a much cooler environment, where temperatures dip to a minimum of -7°C (20°F) and peak at 20°C (68°F), averaging just 4°C (40°F). The precipitation decreases to 79 mm (3.1 in) across 9 days, and humidity is relatively lower at 79%. For a detailed overview of February's weather, you can visit Yamagata weather in February.
In September, the weather is characterized by warm temperatures, with minimums around 12°C (54°F) and maximums soaring to 35°C (95°F), making it a month of summer's lingering heat. Precipitation is relatively high, averaging 298 mm (11.7 in) over 16 days, along with high humidity levels at 87%. In contrast, March experiences a cooler climate, with temperatures ranging from a minimum of -1°C (31°F) to a maximum of 23°C (74°F), averaging around 9°C (48°F). While it sees less rainfall at 179 mm (7.1 in) over 13 days, humidity is lower at 74%. For more details, check Yamagata weather in March.
September weather is characterized by significantly higher temperatures, with averages reaching around 23°C (74°F) while peaking at 35°C (95°F). In contrast, April's temperatures are much cooler, with a maximum of 27°C (82°F) and an average of just 13°C (56°F). Both months experience substantial rainfall, but September receives more precipitation at 298 mm (11.7 in) over 16 days, compared to April's 223 mm (8.8 in) over 12 days. Additionally, humidity is notably higher in September at 87%, compared to 76% in April. For a more detailed look at April weather, you can visit Yamagata weather in April.
September weather features warmer temperatures, with lows around 12°C (54°F) and highs reaching up to 35°C (95°F). In contrast, May tends to be cooler, with minimum temperatures of 5°C (42°F) and maximums peaking at 30°C (87°F). While September experiences higher humidity at 87%, May's humidity is slightly lower at 83%. Precipitation is also more prevalent in September, with 298 mm (11.7 in) falling over 16 days compared to May’s 229 mm (9.0 in) across 12 days. To explore more about conditions in May, visit Yamagata weather in May.
In comparing September and June weather, both months exhibit a similar range of minimum temperatures, with September slightly warmer on average. September boasts an average temperature of 23°C (74°F) compared to June's 22°C (71°F), while the maximum temperatures in September can reach up to 35°C (95°F), surpassing June's high of 31°C (89°F). However, September also experiences significantly more rainfall, with 298 mm (11.7 in) over 16 days, compared to June's 245 mm (9.7 in) over 13 days. Despite the increased precipitation, both months share a high humidity level of 87%, creating a consistently muggy atmosphere. For a more detailed look, you can check Yamagata weather in June.
In comparing the weather between September and July, we can observe notable differences in temperature and precipitation patterns. September offers cooler temperatures, with a minimum of 12°C (54°F) and an average of 23°C (74°F), while July is warmer, featuring a minimum of 18°C (65°F) and an average of 26°C (78°F). Additionally, July experiences higher maximum temperatures, reaching up to 37°C (100°F), compared to September's peak of 35°C (95°F). However, July is significantly wetter, with 493 mm (19.4 in) of precipitation over 22 days, compared to September's 298 mm (11.7 in) over 16 days. The humidity is also slightly higher in July at 93%, compared to 87% in September. For a closer look at July weather in Yamagata, you can read more here: Yamagata weather in July.
In comparison to August, September experiences a slight decrease in temperature with a minimum temperature of 12°C (54°F) and an average of 23°C (74°F), contrasting with August's more humid conditions featuring a minimum of 18°C (64°F) and an average of 27°C (82°F). While both months see significant rainfall, September has a total precipitation of 298 mm (11.7 in) over 16 days, compared to August's 322 mm (12.7 in) over 18 days. Additionally, humidity levels drop slightly in September to 87%, down from August's 91%. For more detailed information, you can check Yamagata weather in August.
September typically experiences warmer temperatures, with minimums around 12°C (54°F) and an average high of 35°C (95°F), while October sees a decrease in warmth, with minimum temperatures dropping to 6°C (43°F) and an average high of 31°C (88°F). Additionally, September is more humid with 87% humidity compared to October's slightly lower 85%. Precipitation is more frequent in September, with 298 mm (11.7 in) falling over 16 days, whereas October has less rainfall at 234 mm (9.2 in) over 14 days. For more details, you can check Yamagata weather in October.
September weather tends to be warmer and more humid, with temperatures ranging from a minimum of 12°C (54°F) to a maximum of 35°C (95°F), averaging around 23°C (74°F). During this month, rain is frequent, with 298 mm (11.7 in) of precipitation spread over 16 days, making it one of the wetter months of the year.
In contrast, November brings a significant drop in temperature, with a range from 1°C (33°F) to 22°C (72°F) and an average of 12°C (53°F). The precipitation also decreases significantly to 74 mm (2.9 in) over just 7 days, and humidity is slightly lower at 83%. For more details on November weather, you can check Yamagata weather in November.
September and December exhibit stark contrasts in weather conditions. In September, temperatures range from a mild 12°C (54°F) at night to a sweltering 35°C (95°F) during the day, accompanied by high humidity levels at 87%. The month experiences significant rainfall, with 298 mm (11.7 in) over 16 days, creating a wet and humid atmosphere. In contrast, December ushers in much cooler temperatures with a low of -5°C (23°F) and a high of just 18°C (65°F), averaging around 6°C (43°F). This month sees considerably less precipitation, totaling 94 mm (3.7 in) over 12 days, and a slight drop in humidity to 83%. For a more detailed look at December weather patterns in Yamagata, visit Yamagata weather in December.
As September unfolds in Yamagata, the weather presents a captivating transition from the sweltering heat of summer to the crisp embrace of autumn. With temperatures averaging a comfortable 23°C, it's a month where warm days can still peak at a toasty 35°C, while cool nights dip to a refreshing 12°C. However, September is also marked by considerable rainfall, with nearly half the month experiencing precipitation, making it one of the wettest times of the year. The high humidity of 87% adds to the atmosphere, contributing to that lush greenery characteristic of the season. For more detailed information on how the weather evolves throughout the year, check out Yamagata Climate.