Last updated: August 21, 2025
In May, Koshi, Japan, experiences a delightful transition into warmer weather, characterized by a maximum temperature of 30°C (86°F) and an average of 19°C (67°F). The temperature can dip to a refreshing minimum of 6°C (43°F), making the month perfect for outdoor activities. However, this beautiful backdrop comes with a notable precipitation amount of 213 mm (8.4 in) over approximately 12 days, contributing to high humidity levels that average around 84%. As spring flourishes, the blend of warmth and occasional rain creates a vibrant environment, inviting exploration and appreciation of the region's natural beauty.
In May, Koshi, Japan, welcomes the warmth of spring with a significant rise in temperatures. The minimum temperature starts at a comfortable 6°C (43°F), and the average climbs to a pleasant 19°C (67°F), peaking at an invigorating 30°C (86°F) during the day. This month stands out as a transitional period; after the chill of winter, May brings a delightful increase in warmth compared to April, where the average was a cooler 15°C (59°F). The trend continues toward the pleasantly warm days of summer, making May an ideal time for outdoor activities and exploration in this charming region. With nature in full bloom and temperatures on the rise, visitors can enjoy the gradual yet vibrant shift into warmer months.
In May, Koshi, Japan, experiences a notable surge in precipitation, accumulating 213 mm (8.4 in) over 12 days of rainfall. This substantial increase from the preceding months highlights May as a pivotal point in the transition toward the region's wetter season. Following a gradual rise in precipitation from 54 mm in January to 132 mm in April, May’s rainfall marks a dramatic escalation, foreshadowing the even heavier downpours of late spring and summer. The combination of increased rainfall days and volume suggests that May is not only a crucial month for replenishing natural water sources but also sets the stage for the impending monsoon months, illustrating the dynamic climate patterns that define Koshi’s weather.
In May, Koshi, Japan, experiences a notable increase in humidity, reaching 84%, the highest level so far this year. This rise signals the transition to the summer months, as the city moves from the moderate humidity of spring to the more oppressive conditions that characterize the summer season. Following May, humidity continues its upward trend, peaking in July at a staggering 92%. The month of April, with its 78% humidity, hints at this impending shift, while May serves as a reminder of the lush, vibrant atmosphere that comes with the approaching warmth. As the summer unfolds, the air in Koshi becomes increasingly saturated, transforming the region into a humid haven.
The UV Index in Koshi, Japan during May remains at an extreme level of 11, identical to the previous month, continuing the trend towards heightened sun exposure as the spring season gives way to warmer weather. With a burn time of just 10 minutes, it’s crucial for residents and visitors alike to take precautions against harmful UV rays. This pattern of high UV levels started in April and shows no signs of let-up, leading into a summer where indices peak. Such intensity emphasizes the importance of adequate sun protection as we transition into June, where the UV Index is expected to sustain similar extremes. For more detailed insights on UV exposure throughout the year, visit Koshi UV Index.
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In Koshi, Japan, the month of May shines the brightest, boasting an impressive 283 hours of sunlight. This delightful increase follows a steady rise from January's modest 178 hours, showcasing the welcoming transition into spring. As the days lengthen from the freshness of March with 259 hours to April's 277 hours, May emerges as a highlight in the sunshine calendar. Beyond May, the sun continues to bless the region, though in a gradual decline through the summer and fall, reaching 294 hours in August before tapering to 232 hours by November. This pattern not only highlights the warming embrace of longer days in late spring but also sets the stage for the lush landscapes of Koshi to flourish under the generous May sun.
As spring transitions into summer, the likelihood of sunny weather in Koshi, Japan sees a notable shift. May presents a sunny chance of only 28%, marking a dip from the slightly higher probabilities found in the preceding months, such as 43% in April. This decline continues into the sweltering months ahead, with June dropping to a mere 22%, illustrating a trend toward cloudier skies. In contrast, the autumn months reveal a resurgence of sunny days, peaking at 64% in October. Overall, while May may offer some lovely days, those seeking consistent sunshine might want to plan their visits for later in the year when the sun shines more reliably.
In Koshi, Japan, the progression of daylight throughout the year reveals a captivating trend of increasing brightness as spring transitions into summer. Starting in January and February with a modest 10 hours of daylight, the days gradually lengthen, giving way to 11 hours in March and 12 hours in April. May stands out with 13 hours of daylight, marking a vibrant awakening of the season. This trend continues, peaking at 14 hours in both June and July, where the days are at their longest, basking the region in abundant sunlight. As summer wanes, daylight begins to retreat, with August dipping back to 13 hours and September to 12 hours. By the time October arrives, daylight returns to 11 hours, before settling back to 10 hours in the final months of the year. This rhythm of daylight not only signifies the changing seasons but also encourages a deeper appreciation of nature's cycles in Koshi.
In Koshi, Japan, the wind in May delivers a gentle average speed of 2.4 m/s (5 mph), mirroring the soft breezes seen in the preceding months of January, April, and March. As spring unfolds, the winds remain relatively stable, creating a serene atmosphere perfect for outdoor activities and exploration. This continuity contrasts with the lighter gusts of June, which dips to 1.6 m/s (4 mph), suggesting a transition towards calmer summer days. Overall, May encapsulates a mild and pleasant wind pattern, encouraging residents and visitors alike to savor the beauty of the blooming season as the air remains refreshing yet unobtrusive.
Weather in Koshi varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Koshi, focusing on differences in temperature, rainfall, humidity, and UV levels.
May and January present strikingly different weather patterns. In May, temperatures range from a cool 6°C (43°F) to a warm 30°C (86°F), with an average of 19°C (67°F), while January sees much colder temperatures, with a minimum of -5°C (24°F) and a maximum of 17°C (63°F) and an average of only 6°C (42°F). Additionally, May is significantly wetter, receiving 213 mm (8.4 in) of rainfall over 12 days compared to January's 54 mm (2.1 in) across just 6 days. The humidity is also higher in May at 84%, while January maintains a lower humidity level of 75%. For more detailed insight into January weather, visit Koshi weather in January.
In comparing the weather between February and May, notable differences emerge. February experiences much colder temperatures, with a minimum of -5°C (24°F) and an average of 7°C (44°F), whereas May warms up significantly, featuring a minimum of 6°C (43°F) and an average temperature of 19°C (67°F). Additionally, May tends to be much wetter, with 213 mm (8.4 in) of precipitation over about 12 days, compared to the 96 mm (3.8 in) recorded in February over 10 days. Humidity levels also differ, with May reaching 84% compared to February's 71%. For a detailed look at weather conditions in February, you can visit Koshi weather in February.
In comparing the weather between March and May, we see a significant difference in temperature and humidity levels. May features a much warmer range, with average temperatures soaring up to 19°C (67°F) and maximums hitting 30°C (86°F), while March has a cooler average of 11°C (52°F), with max temperatures only reaching 24°C (75°F). Furthermore, May is characterized by higher humidity at 84%, compared to March's 71%. Precipitation is also notably greater in May, with 213 mm (8.4 in) of rain over 12 days, compared to March's 131 mm (5.2 in) during the same number of days. For a more detailed look at the weather conditions in March, check out Koshi weather in March.
In comparing the weather between May and April, May typically offers warmer temperatures, with an average of 19°C (67°F) compared to April's 15°C (59°F). The minimum temperature in May is also notably higher at 6°C (43°F) versus April's 1°C (34°F). However, despite the warmer conditions, May experiences increased precipitation, with 213 mm (8.4 in) of rain over 12 days, while April sees only 132 mm (5.2 in) over 9 days. The humidity in May is slightly higher at 84%, compared to April's 78%. For more details on the weather in April, check out Koshi weather in April.
May and June exhibit noticeable differences in weather patterns. May starts off with cooler temperatures, ranging from a minimum of 6°C (43°F) to a maximum of 30°C (86°F), averaging around 19°C (67°F). The month experiences significant precipitation, with 213 mm (8.4 in) falling over 12 days, resulting in a humidity level of 84%. In contrast, June warms up, with temperatures ranging from a minimum of 13°C (55°F) to a peak of 32°C (89°F), averaging at 23°C (73°F). This month also sees an increase in precipitation to 274 mm (10.8 in) over 15 days, and humidity slightly rises to 86%. For more detailed weather information, you can check Koshi weather in June.
In May, temperatures range from a cool 6°C (43°F) to a warm 30°C (86°F), with an average of 19°C (67°F). The month experiences 213 mm (8.4 in) of precipitation over approximately 12 days, and humidity levels are relatively high at 84%. In contrast, July sees significantly warmer temperatures, with minimums around 17°C (63°F) and maximums peaking at 35°C (96°F), averaging 26°C (79°F). However, July is also marked by increased rainfall, totaling 478 mm (18.8 in) over about 20 days, and even higher humidity levels at 92%. For more detailed insights into July weather, you can refer to this link: Koshi weather in July.
May and August present distinct weather contrasts, particularly in temperature and precipitation. In May, temperatures range from a cooler minimum of 6°C (43°F) to a comfortable average of 19°C (67°F), peaking at 30°C (86°F). The month sees significant rainfall, with a total precipitation of 213 mm (8.4 in) over 12 days and an average humidity of 84%. Conversely, August experiences much warmer temperatures, starting at a minimum of 18°C (65°F) and averaging 28°C (82°F), with highs reaching up to 35°C (96°F). This month also brings increased rainfall of 277 mm (10.9 in) spread over 15 days, along with higher humidity at 91%. For more detailed insights into the August weather, you can check Koshi weather in August.
May and September present contrasting yet enjoyable weather conditions. In May, temperatures range from a cool 6°C (43°F) at night to a warm 30°C (86°F) during the day, with an average of 19°C (67°F). However, May is quite wet, experiencing 213 mm (8.4 in) of precipitation over about 12 days, contributing to high humidity levels of 84%.
In comparison, September offers warmer evenings with a minimum temperature of 12°C (53°F) and higher daytime highs reaching up to 34°C (94°F), averaging at 24°C (76°F). While it is slightly drier than May, September still sees substantial rainfall of 184 mm (7.2 in) over approximately 14 days, maintaining the same relative humidity of 84%. For a detailed look at September's climate, you can check this link: Koshi weather in September.
May and October share some similarities in their weather, particularly in temperature averages, which hover around 19°C (66°F). May tends to experience a broader temperature range, with maximum highs reaching up to 30°C (86°F), while October can peak at 31°C (88°F). Precipitation is notably higher in May, with about 213 mm (8.4 in) occurring over 12 days compared to October's 107 mm (4.2 in) over just 8 days. Both months maintain high humidity levels, with May at 84% and October slightly lower at 83%. For more insights on how the weather unfolds in October, check out Koshi weather in October.
May and November exhibit distinct differences in weather patterns. May generally enjoys warmer temperatures, with a minimum of 6°C (43°F) and an average high of 30°C (86°F), while November sees cooler conditions, with temperatures ranging from -1°C (30°F) to a maximum of 25°C (77°F). Precipitation levels are notably higher in May, averaging 213 mm (8.4 in) over 12 days, compared to November's more modest 60 mm (2.4 in) over just 7 days. Although humidity remains relatively high in both months, May's 84% slightly surpasses November's 81%. For a closer look at the weather conditions during November, you can visit Koshi weather in November.
May and December showcase distinct weather patterns, reflecting the transition between spring and winter. In May, temperatures are pleasantly warm, averaging around 19°C (67°F) with highs reaching up to 30°C (86°F). However, the month also sees significant rainfall, accumulating to 213 mm (8.4 in) over about 12 days, contributing to a high humidity level of 84%. In contrast, December experiences much cooler temperatures, with an average of 7°C (45°F) and maximums of 22°C (72°F). Precipitation decreases significantly to 71 mm (2.8 in) over just 7 days, accompanied by a relative humidity of 79%. For more detailed insights into December weather, visit Koshi weather in December.
As May unfolds in Koshi, the temperatures typically rise, showcasing warmer days that stand in contrast to the cooler, brisk months preceding it. With an average temperature nudging toward a pleasant 19°C, this month invites outdoor activities, yet it also brings increased humidity at around 84%. May is characterized by its notable rainfall, with precipitation spread across about 12 days, contributing to a lush landscape as spring blooms. This shift to warmer and wetter conditions sets the stage for the vibrant transitions into summer, making it an exciting time to experience the region's natural beauty. For more insights into the weather patterns, check out Koshi Climate.