Last updated: August 21, 2025
September in Yokohama, Japan, presents a vibrant blend of warm temperatures and notable humidity. With a maximum of 32°C (90°F) and an average of 24°C (76°F), residents and visitors can expect balmy days, occasionally cooling down to a minimum of 16°C (60°F). However, this month is also characterized by significant rainfall, totaling 187 mm (7.4 in) across 16 days, making it advisable to carry an umbrella. The humidity levels hover around a sultry 86%, adding to the tropical feel of the season. Embrace the dynamic weather while exploring the vibrant surroundings of Yokohama, a city rich in culture and scenic beauty.
In September, Yokohama experiences a welcomed transition from the swelter of summer to the mildness of autumn. With a minimum temperature of 16°C (60°F) and an average soaring to 24°C (76°F), the city is enveloped in comfortably warm days, perfect for exploring its vibrant streets. As the month progresses, highs can reach up to 32°C (90°F), still reminiscent of the summer heat but tempered by the onset of seasonal changes. This gradual cooling trend stands in stark contrast to the preceding months, where July and August peak at around 35°C (95°F) and 34°C (93°F) respectively. As September unfolds, the weather not only invites outdoor activities but also sets the stage for the picturesque beauty of autumn that follows.
September in Yokohama, Japan, captures the transition from summer's intense heat to the onset of autumn's cooler embrace. With an impressive 187 mm (7.4 in) of rainfall over 16 days, this month stands out as one of the wetter periods, reflecting a pattern that typically peaks just before October's rainfall escalation. Compared to the preceding summer months, where July was notably the wettest at 209 mm (8.2 in), September's precipitation indicates a slight dip yet remains substantial, suggesting the region's shift towards a rainier climate. This trend highlights the transitionary nature of September, as it balances lingering summer storms with early autumn weather, impacting both the landscape and daily life in the vibrant city.
In September, Yokohama experiences a notable shift in humidity, with levels averaging 86%. This places it slightly lower than the peak summer months of July and August, which see humidity soar to 93% and 90%, respectively. However, September remains quite humid compared to earlier months in the year, reflecting the lingering effects of summer's warmth. After a gradual increase from 74% in February to the summer's highs, humidity begins its slow decline, providing a hint of relief as autumn approaches. This seasonal transition highlights Yokohama's unique climate rhythm, where humidity levels remain relatively high well into the fall.
As September rolls in, Yokohama experiences a significant drop in UV intensity compared to the peak summer months, but it still reaches a very high index of 10. With a burn time of just 15 minutes, it's crucial to remain vigilant against the sun's rays during this time. The trend from August's extreme conditions continues, showcasing the lingering summer heat that blends into early autumn. Interestingly, following the consistent extreme levels from May through August, September serves as a reminder that UV risks remain high even as temperatures begin to cool. For more detailed insights on UV exposure throughout the year, check out Yokohama UV Index.
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As the summer warmth gradually transitions to the crispness of autumn, Yokohama experiences a delightful September with an impressive 235 hours of sunshine. This month stands out as a serene pause following the sun-drenched days of August, which boasts the highest sunshine hours at 288. While September's totals reflect a minor dip, they remain significantly robust compared to early months like January and February, which see only 191 and 233 hours, respectively. The trend reveals a gradual build-up of sunlight leading into the vibrant blooms of spring, peaking during the summer and settling into a comfortable rhythm in early fall. As the city's residents bask in this September glow, the gentle sunlight serves as a beautiful transition, bridging the vibrant vitality of summer with the soft hues of autumn.
September in Yokohama sees a notable dip in sunny weather, with only a 28% chance of sunshine, making it one of the cloudier months of the year. This trend marks a significant decline from the sunnier spring months, with April and October both boasting a 50% chance of sun. Interestingly, as summer transitions to autumn, the likelihood of clear skies decreases steadily, reflecting a typical shift in weather patterns. Just after the hot summer months of July and August, which only offered 34% and 37% sunny days respectively, September seems to continue the trend of overcast conditions, highlighting the need for those visiting to be prepared for potentially gloomy weather.
As the summer sun begins to wane, September in Yokohama brings approximately 12 hours of daylight, marking a gentle transition towards shorter days. Following the peak of 14 hours in both June and July, daylight gradually diminishes through August and into the early autumn months. This gradual decline not only signifies the end of summer's exuberance but also sets the stage for the more subdued daylight hours of the coming fall and winter. As the days grow shorter, residents can savor the shift in seasons, enjoying the unique beauty that September’s softer light brings to the city.
In September, Yokohama experiences a gentle breeze, with an average wind speed of 4.4 m/s (10 mph). This marks a slight increase from the quieter summer months of July and August, suggesting a transition into the more dynamic autumn season. As the year unfolds, wind speeds tend to fluctuate, peaking at 5.3 m/s (12 mph) in May before dipping during the humid summer months. By the time September comes around, the winds begin to regain their rhythm, signaling a shift in the atmosphere and inviting residents and visitors alike to enjoy the refreshing air as the city gears up for the vibrant fall months ahead.
Weather in Yokohama varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Yokohama, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present strikingly different weather patterns. In September, temperatures range from a mild 16°C (60°F) at night to a warm average of 24°C (76°F) during the day, peaking at a hot 32°C (90°F). This month is also characterized by high humidity at 86% and considerable rainfall, with 187 mm (7.4 in) of precipitation spread over 16 days. In contrast, January experiences a chillier climate, with temperatures dipping as low as -3°C (27°F) at night and averaging just 6°C (44°F) throughout the day, reaching a maximum of 18°C (65°F). Additionally, January sees significantly less precipitation, totaling only 52 mm (2.1 in) over just 4 days, and a lower humidity level at 76%. For a detailed overview of January weather in Yokohama, you can visit Yokohama weather in January.
September and February present a stark contrast in weather conditions. September experiences warmer temperatures, with minimums around 16°C (60°F) and maximums peaking at 32°C (90°F), while February sees much cooler temperatures, ranging from a chilly 0°C (31°F) to a milder 18°C (66°F). Precipitation is significantly higher in September, totaling 187 mm (7.4 in) over 16 days, compared to a more manageable 43 mm (1.7 in) across just 7 days in February. Additionally, the humidity in September is notably higher at 86%, while February maintains a lower humidity level of 74%. For more detailed information, you can check Yokohama weather in February.
In comparing the weather of September and March, we can observe significant differences in temperature and humidity. September boasts a warmer climate with minimum temperatures around 16°C (60°F), averaging 24°C (76°F), and reaching highs of 32°C (90°F). Conversely, March is much cooler, with minimum temperatures plummeting to 1°C (34°F) and an average of only 11°C (52°F), topping out at 20°C (69°F). Additionally, September experiences higher humidity at 86% and more rainfall, with 187 mm (7.4 in) over 16 days, compared to March's 70% humidity and 138 mm (5.4 in) over just 12 days. For more specific details about March weather patterns in Yokohama, you can refer to Yokohama weather in March.
September weather is typically warm and humid, with average temperatures ranging from a minimum of 16°C (60°F) to a maximum of 32°C (90°F) and a high humidity level of 86%. The month experiences significant rainfall, with about 187 mm (7.4 in) of precipitation spread over 16 days. In contrast, April sees much cooler conditions, with temperatures ranging from a low of 4°C (40°F) to a high of 23°C (74°F) and an average temperature of 15°C (58°F). The precipitation in April is also lower, totaling 116 mm (4.6 in) over approximately 10 days, accompanied by a humidity level of 74%. For more details on April's weather, you can visit Yokohama weather in April.
September in Yokohama brings warm temperatures, with minimums around 16°C (60°F) and average highs reaching up to 32°C (90°F), making it significantly warmer than May, which has a cooler average of 19°C (67°F) with maximum temperatures peaking at 27°C (80°F). Additionally, September experiences a higher level of precipitation, averaging 187 mm (7.4 in) over 16 days, compared to May's 118 mm (4.6 in) over just 11 days. The humidity levels are also slightly elevated in September at 86%, in contrast to May’s 81%. For a detailed look at May weather patterns, you can visit Yokohama weather in May.
September typically features warmer temperatures compared to June, with average highs reaching 32°C (90°F) and lows around 16°C (60°F), while June’s averages are slightly cooler, peaking at 29°C (85°F) with a similar low of 16°C (61°F). Additionally, September experiences more rainfall, totaling 187 mm (7.4 in) over 16 days, which is higher than June's 161 mm (6.3 in) across 13 days. Humidity levels are slightly lower in September at 86%, compared to June's 88%, making September feel a bit more comfortable despite the increased rainfall. For more details on June weather, you can visit Yokohama weather in June.
When comparing the weather in September to July, it’s clear that September presents slightly cooler temperatures, with an average of 24°C (76°F) compared to July’s warmer average of 26°C (78°F). In terms of extremes, July boasts higher maximum temperatures, reaching up to 35°C (95°F), whereas September peaks at 32°C (90°F). Precipitation levels are also noteworthy; July experiences a total of 209 mm (8.2 in) over 16 days, slightly higher than September’s 187 mm (7.4 in) on the same number of days. Additionally, humidity is greater in July at 93%, compared to 86% in September. For a more detailed look, you can check out Yokohama weather in July.
In comparing the weather between August and September, September experiences slightly cooler temperatures, with a minimum of 16°C (60°F) and an average of 24°C (76°F), contrasting with August's warmer minimum of 20°C (68°F) and average of 28°C (82°F). Furthermore, September sees increased precipitation, totaling 187 mm (7.4 in) over 16 days, compared to August's 104 mm (4.1 in) across 12 days. Humidity levels are also high in both months, with September at 86% and August at 90%. For a more detailed exploration of August weather in the region, visit Yokohama weather in August.
September and October present a noticeable shift in weather patterns. In September, temperatures range from a comfortable minimum of 16°C (60°F) to a warm maximum of 32°C (90°F), with an average of 24°C (76°F). This month also sees significant rainfall, accumulating to 187 mm (7.4 in) over 16 days and high humidity levels at 86%. In contrast, October brings cooler temperatures, with a minimum of 11°C (52°F), a maximum of 28°C (83°F), and an average temperature of 19°C (67°F). While October has even higher precipitation, totaling 266 mm (10.5 in) over the same 16 days, the humidity slightly decreases to 83%. For more details on October weather patterns, you can visit Yokohama weather in October.
September and November present a stark contrast in weather conditions. September typically sees warmer temperatures, with a minimum of 16°C (60°F) and an average high of 32°C (90°F), while November cools down significantly, with temperatures ranging from a minimum of 4°C (40°F) to a maximum of 23°C (73°F). Additionally, September is much wetter, boasting 187 mm (7.4 in) of precipitation over 16 days compared to November's 87 mm (3.4 in) spread over just 11 days. Humidity is also slightly higher in September at 86%, while November sits at a more comfortable 80%. For more detailed information about weather patterns, you can check Yokohama weather in November.
September and December present strikingly different weather conditions. In September, the temperatures are warm, with a minimum of 16°C (60°F) and an average of 24°C (76°F), peaking at 32°C (90°F), coupled with high humidity at 86%. The month also sees significant rainfall, with precipitation totaling 187 mm (7.4 in) over 16 days. In contrast, December is much cooler, with temperatures ranging from a minimum of 0°C (33°F) to a maximum of 21°C (70°F) and an average of only 9°C (49°F). The precipitation decreases substantially to 64 mm (2.5 in) spread over just 7 days, and humidity drops to 78%. For those looking to learn more about the December weather in Yokohama, you can explore Yokohama weather in December.
As summer transitions to autumn, Yokohama's September weather presents a unique blend of warmth and humidity, making it distinct from other months. With temperatures swinging from warm highs to cooler lows, the city maintains an average that invites both locals and travelers to explore its vibrant streets. However, the month is also marked by frequent rainfall, with many days experiencing precipitation, contributing to the lush greenery of the region. The high humidity can make the atmosphere feel more intense, yet it adds to the charm of September in Yokohama. For a more detailed look at what to expect, be sure to check out Yokohama Climate.