Last updated: August 21, 2025
In Koshima, Japan, December brings a blend of mild temperatures and increased precipitation, making it a unique winter destination. With a maximum temperature reaching 24°C (75°F) and an average of 16°C (61°F), the climate remains comfortably warm, while the minimum temperature can dip to 8°C (46°F). However, visitors should prepare for the rainy season, as the month records approximately 132 mm (5.2 in) of rainfall over 14 days, accompanied by a humidity level of 74%. This combination of warmth and moisture creates a lush, vibrant landscape, perfect for exploring Koshima's natural beauty during the festive season.
In Koshima, Japan, December marks a subtle transition towards the cooler months, with temperatures reflecting a comfortable range for winter. The month sees a minimum of 8°C (46°F), offering a crisp but manageable chill, while the average temperature settles around 16°C (61°F). As the festive season approaches, highs can reach up to 24°C (75°F), providing a pleasant backdrop for outdoor activities. Compared to the preceding months, December stands out with a noticeable dip in minimum temperatures from 13°C (56°F) in November, yet still maintains a friendly warmth during the day. Overall, December in Koshima beautifully balances the refreshing briskness of winter with mild daytime warmth, making it an inviting time to explore the region.
In Koshima, Japan, December ushers in a moderate precipitation pattern, with 132 mm (5.2 in) of rain falling over approximately 14 days. As the year winds down, this month's rainfall showcases a slight decline compared to the preceding months, particularly November's 150 mm and October's 164 mm. The trend reflects a gradual easing of the rainy season, yet December remains a significant contributor to the overall annual total. This consistent moisture sets the stage for the region's lush landscapes, even as temperatures drop, making Koshima's winter both refreshing and vibrant.
In Koshima, Japan, December marks a moderate shift in humidity, with levels averaging 74%. This figure follows a seasonal trend characterized by rising moisture as the year progresses, peaking during the summer months of June and July at a steamy 86% and 90% respectively. After the summer's high humidity, the late fall and early winter months—November and December—bring a slight decline, though levels remain notable. Typically, December's humidity showcases a return to more comfortable, yet still humid conditions, bridging the transition into the cooler months of January and February, where the average dips to 72% and 68% respectively. Overall, Koshima's humidity exhibits a predictable pattern, reflecting the region's unique climatic rhythm throughout the year.
In December, Koshima, Japan experiences a notable decrease in UV exposure, with the UV Index dropping to 5, placing it in the moderate category. This shift provides a welcome respite from the extreme levels seen during the summer months, where the index peaked at 13 in July and August. As winter sets in, the burn time increases to 30 minutes, allowing for more leisurely outdoor activities without the immediate risk of sunburn. This seasonal trend underscores the importance of staying informed about UV levels throughout the year. For more detailed information, check the Koshima UV Index.
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In Koshima, Japan, December marks the transition from the vibrant, sun-drenched days of summer to the cooler embrace of winter, with 204 hours of sunshine casting a gentle glow over the city. While December experiences fewer sunlit hours compared to the peak brightness of August, which boasts a remarkable 319 hours, it still reflects a robust annual average, trailing only slightly behind November's 238 hours. This gradual decline from the sunniest months showcases a trend of diminishing sunlight as the year draws to a close, yet the lingering warmth of daylight continues to infuse the chilly winter air with a hint of radiance, inviting residents and visitors alike to savor the crisp, sunlit moments of the season.
In Koshima, Japan, the likelihood of enjoying sunny weather in December stands at 30%, which is slightly below the average for the autumn months. As the year progresses from October's peak 53% chance of sunshine, the shift towards winter brings a gradual decline in sunny days. Notably, December's sunlit opportunities fall behind the sunnier months of September and November, where the chances are 46% and 38%, respectively. This trend illustrates a seasonal transition, suggesting that while December isn't the sunniest time of year, it still offers a glimmer of daylight amidst the encroaching chill of winter.
In Koshima, Japan, the daylight hours experience a dynamic ebb and flow throughout the year. Starting from 10 hours in January, daylight gradually increases to a peak of 14 hours in June, enveloping the area in bright, sunlit days as spring transitions into summer. Following this high, daylight hours begin to taper off, settling back to 10 hours again by December. The rhythm of longer days in spring and summer gives way to shorter, cozy evenings in the autumn and winter months, creating a picturesque seasonal transition that reflects the natural cycle of light and dark in this charming region.
As December settles over Koshima, Japan, the wind picks up slightly, averaging 8.5 m/s (19 mph), a mild increase from November's 8.4 m/s (19 mph). This winter month contrasts with the calmer breezes of summer, where speeds dipped to as low as 6.3 m/s (14 mph) in June. The trend throughout the year shows a gradual rise from the softer spring winds, peaking during the cooler months, suggesting that as the temperatures drop, the wind's presence becomes more pronounced. December stands out with its consistent gusts, inviting both residents and visitors to embrace the crisp, invigorating air of the season.
Weather in Koshima varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Koshima, focusing on differences in temperature, rainfall, humidity, and UV levels.
In December, temperatures in Koshima range from a minimum of 8°C (46°F) to a maximum of 24°C (75°F), with an average of 16°C (61°F). The month experiences considerable rainfall, totaling 132 mm (5.2 in) across 14 days, and a humidity level of 74%. In contrast, January sees slightly cooler temperatures, with a minimum of 6°C (44°F) and a maximum of 21°C (70°F), averaging 14°C (57°F). Precipitation decreases to 108 mm (4.2 in) over 12 days, and humidity is marginally lower at 72%. For more specific details, you can check Koshima weather in January.
In December, temperatures range from a minimum of 8°C to a maximum of 24°C, with an average of 16°C, while February experiences slightly cooler conditions with a minimum of 7°C and a maximum of 21°C, averaging at 14°C. Additionally, December sees more precipitation, totaling 132 mm over 14 days, compared to February's 157 mm spread across 16 days. Despite the increased rainfall in February, the humidity is lower at 68%, whereas December has a higher humidity level of 74%. For a detailed look at February's weather in Koshima, you can visit Koshima weather in February.
December weather features a range of temperatures with a minimum of 8°C (46°F) and a maximum of 24°C (75°F), averaging around 16°C (61°F). The month also experiences significant rainfall, totaling 132 mm (5.2 in) over approximately 14 rainy days, accompanied by a humidity level of 74%. In contrast, March sees slightly warmer conditions with minimum temperatures of 10°C (51°F) and a slightly lower maximum of 22°C (72°F), while still averaging around 16°C (62°F). However, this month is notably wetter, with 213 mm (8.4 in) of precipitation across about 16 days, and humidity remains relatively stable at 72%. For a detailed look at March weather, you can check out Koshima weather in March.
When comparing the weather in December and April, notable differences emerge in terms of temperature and precipitation. December's temperatures range from a minimum of 8°C (46°F) to a maximum of 24°C (75°F), with an average of 16°C (61°F). In contrast, April sees slightly warmer conditions, with minimum temperatures at 12°C (53°F) and an average of 19°C (66°F), while still maintaining a peak of 24°C (75°F). Precipitation is more pronounced in April, with 186 mm (7.3 in) falling over 12 days, compared to December’s 132 mm (5.2 in) across 14 days. Additionally, humidity levels are slightly higher in April at 79%, compared to December's 74%. For more specific details, you can check Koshima weather in April.
December and May present distinctly different weather patterns. In December, temperatures range from a cool 8°C (46°F) at night to a comfortable maximum of 24°C (75°F) during the day, accompanied by an average humidity of 74%. The month is relatively wet, with 132 mm (5.2 in) of precipitation over 14 days. In contrast, May enjoys warmer temperatures, with nighttime lows of 16°C (61°F) and daytime highs reaching 26°C (78°F). However, it is also the wetter month, receiving 273 mm (10.7 in) of rain over 13 days and a higher humidity of 83%. For more detailed information on weather specifics in May, check out Koshima weather in May.
When comparing the weather in December and June, it's evident that June is significantly warmer and wetter. December experiences milder temperatures, with a minimum of 8°C (46°F) and a maximum of 24°C (75°F), whereas June has a much higher temperature range, from 19°C (67°F) to 27°C (81°F). Additionally, June sees substantially more rainfall, with 491 mm (19.3 in) of precipitation over 19 days, compared to December's 132 mm (5.2 in) over 14 days. The humidity is also higher in June at 86%, compared to December's 74%. For more details on June weather patterns, you can visit Koshima weather in June.
December and July present contrasting weather conditions. In December, temperatures range from a mild 8°C (46°F) at night to a comfortable average of 16°C (61°F) during the day, peaking at 24°C (75°F). The month sees 132 mm (5.2 in) of precipitation over 14 days, with a humidity level of 74%. In stark contrast, July boasts much warmer temperatures, with nighttime lows at 23°C (73°F) and daytime averages reaching 27°C (81°F), maxing out at 30°C (86°F). July experiences higher rainfall, totaling 281 mm (11.0 in) over 17 days, along with increased humidity at 90%. For more detailed information about the weather during this summer month, you can check Koshima weather in July.
In December, Koshima experiences milder temperatures, with a minimum of 8°C (46°F) and an average of 16°C (61°F), peaking at 24°C (75°F). The month is characterized by frequent rain, averaging 132 mm (5.2 in) over 14 days, and a humidity level of 74%. In contrast, August brings much warmer weather, with temperatures ranging from a minimum of 24°C (76°F) to an average of 28°C (82°F) and a high of 30°C (86°F). The summer month also sees increased precipitation, totaling 214 mm (8.4 in) across 16 days, along with higher humidity at 85%. For more details on weather specifics, check out Koshima weather in August.
In comparing the weather of December and September, December features cooler temperatures with a minimum of 8°C (46°F) and an average of 16°C (61°F), while September boasts much warmer conditions, starting at a minimum of 22°C (72°F) and averaging around 27°C (80°F). Precipitation also differs significantly; December receives 132 mm (5.2 in) over 14 days, whereas September sees a substantial 256 mm (10.1 in) over 20 days. Additionally, the humidity levels are relatively high in both months, with December at 74% and September slightly higher at 80%. For more detailed insights on September weather, check out Koshima weather in September.
When comparing the weather in December to October, several notable differences emerge. December experiences cooler temperatures, with an average of 16°C (61°F) compared to October's warmer average of 24°C (75°F). The minimum and maximum temperatures in December range from 8°C (46°F) to 24°C (75°F), whereas October maintains a milder range of 18°C (65°F) to 27°C (81°F). Additionally, December has higher precipitation, totaling 132 mm (5.2 in) over 14 days, while October sees slightly more rain at 164 mm (6.4 in) over 13 days. Humidity levels are also higher in October at 78%, compared to 74% in December. For more detailed information about October’s weather, you can visit Koshima weather in October.
In comparison to November, December experiences a noticeable drop in morning temperatures, with minimums averaging 8°C (46°F) compared to November's 13°C (56°F). However, December's average high of 24°C (75°F) remains quite similar to November's peak of 25°C (78°F). Precipitation slightly decreases in December, with 132 mm (5.2 in) over 14 days, while November sees a bit more rain at 150 mm (5.9 in) over 13 days. Humidity levels are also marginally lower in December at 74%, compared to November's 76%. For more details, you can check out Koshima weather in November.
As December settles in Koshima, the weather takes on a distinct character compared to the rest of the year. Temperatures are milder, with a comfortable average that invites outdoor exploration, yet the cooler nights remind us that winter is approaching. This month also sees a notable increase in precipitation, with several rainy days contributing to the lush landscapes that Koshima is known for. The humidity remains high, creating a unique atmosphere that enhances the vibrant greenery. For a deeper dive into how these conditions fit within Koshima’s yearly weather patterns, check out Koshima Climate.