Last updated: August 21, 2025
December in Koshi, Japan brings a unique blend of wintry charm and mild temperatures. The maximum temperature reaches a pleasant 22°C (72°F), while the average cools down to 7°C (45°F), dipping to a chilly minimum of -2°C (29°F) overnight. Visitors can expect 71 mm (2.8 in) of precipitation over approximately 7 days, resulting in a distinctly humid atmosphere at 79%. This month is perfect for embracing the seasonal shifts, with occasional rain adding to the serene winter landscape while maintaining a comfortable outdoor experience.
In Koshi, Japan, December marks a transition into the heart of winter, where temperatures tend to dip, showcasing a fascinating shift as the year draws to a close. The month begins with a minimum temperature of -2°C (29°F), rising to an average of 7°C (45°F), and peaking at a pleasant 22°C (72°F) during the day. This fluctuation highlights the typical late-year chill, as the city experiences cooler nights and moderately warm afternoons. Notably, these temperatures contrast sharply with the milder conditions of earlier months, such as October and November, where averages hovered around 12°C (55°F) to 19°C (66°F). As winter tightens its grip, December's crisp air and varied temperatures set the stage for seasonal festivities and the beauty of the snowy landscapes that Koshi is well-known for.
December in Koshi, Japan, brings a modest precipitation total of 71 mm (2.8 inches), marking a slight uptick from November's 60 mm. Rainfall during this month occurs over approximately 7 days, maintaining a pattern of reduced precipitation as the year draws to a close. While December's totals are notably lower compared to the peak summer months—such as July, which records a staggering 478 mm (18.8 inches)—the gradual decline in rainfall from the previous months signals a transition into the drier winter season. As the landscape transitions, the crisp air and occasional rain can offer a serene backdrop to Koshi's natural beauty, enhancing the area's winter charm.
As the year comes to a close, December in Koshi, Japan, showcases a humidity level of 79%, a slight dip from the preceding months while still remaining relatively high. This month typically sees humidity levels begin to decrease after a peak in the summer, where July and August experience the highest humidity, reaching 92% and 91%, respectively. Interestingly, December’s levels continue to reflect the trend of remarkable moisture retention seen throughout the year, especially in the warmer months, which peaked in June with 86% humidity. Moreover, as we transition from the lush spring months, with May at 84%, the gradual decline signals the onset of winter, but still maintains a significant atmospheric humidity that's characteristic of Koshi’s climate.
The UV Index in Koshi, Japan experiences distinct fluctuations throughout the year, peaking in the summer months. As December rolls in, the UV Index dips to a moderate 4, allowing for a more leisurely outdoor experience with a burn time of around 30 minutes. This is a refreshing contrast to the extreme levels observed from April to August, where the Index hits as high as 12, demanding quick protective measures with burn times plummeting to just 10 minutes. As we transition from the vibrancy of summer to the cooler winter months, the UV index retracts significantly, signaling a time to enjoy the outdoors more safely. For those planning activities, it's beneficial to stay informed on the ever-changing UV levels throughout the year. For more details, check out Koshi UV Index.
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December in Koshi, Japan, experiences a gentle transition into winter, with an average of 218 hours of sunlight gracing the days. While the month sees less sunshine compared to the vibrant summer peaks, particularly August's impressive 294 hours, it still maintains a respectable amount of light as the year comes to a close. The gradual decline in daylight hours from October's 247 hours reflects the seasonal shift, yet December's sunshine remains a reminder of warmth during the cold months. With sunshine hours steadily rising from January’s 178 hours to December, Koshi beautifully showcases the ebb and flow of daylight throughout the year, inviting residents to celebrate the rich tapestry of changing seasons.
In December, Koshi, Japan experiences a 51% chance of sunny weather, mirroring the trend seen in November. As the year winds down, there is a notable increase in sunny days compared to the summer months, where the likelihood drops to a mere 18% in July. This gradual improvement in sunshine extends from October’s impressive 64%, showcasing a seasonal shift that favors clearer skies as winter approaches. December stands out as a balanced month, offering a mix of calm, sunny days amid the chill, providing a charming winter ambiance for visitors and residents alike.
In Koshi, Japan, the daylight duration exhibits a clear seasonal rhythm that aligns with the changing months. Starting the year with a steady 10 hours of daylight in both January and February, the days gradually lengthen through March, reaching 12 hours in April and peaking at 14 hours during the vibrant summer months of June and July. As August transitions back to 13 hours, a gradual decline begins, reflecting the autumn shift. By December, daylight returns to 10 hours, mirroring the early winter's start. This cyclical pattern highlights the intricate interplay between the seasons, illustrating not only the beauty of nature's timetable but also the comforting predictability of daylight in Koshi throughout the year.
As December settles over Koshi, Japan, the wind begins to pick up slightly from its mid-year lows, averaging 2.4 m/s (5 mph). This increase is a gentle ramp-up from the calm of summer and the slightly breezy autumn months, indicating a transition into winter. Compared to earlier months, such as June, when the wind barely rustled at 1.6 m/s (4 mph), December’s conditions evoke a sense of the season's chill, without becoming overwhelming. Notably, the overall trend reveals a pattern of consistent, mild breezes throughout the year, punctuated by slightly stronger currents that breathe life into the natural landscape as it moves into the colder months. With the wind aligning itself just above the calmest periods, December offers a serene yet invigorating atmosphere, perfect for appreciating the stunning winter vistas of Koshi.
Weather in Koshi varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Koshi, focusing on differences in temperature, rainfall, humidity, and UV levels.
December and January present a notable shift in weather, with January generally being colder than December. In December, temperatures range from a minimum of -2°C (29°F) to a maximum of 22°C (72°F), averaging around 7°C (45°F). The month experiences a higher level of precipitation at 71 mm (2.8 in) over 7 days, coupled with a humidity level of 79%. In contrast, January sees a further drop in temperatures, with minimums falling to -5°C (24°F) and maximums peaking at 17°C (63°F), averaging 6°C (42°F). Precipitation decreases to 54 mm (2.1 in) spread over 6 days, and humidity slightly lowers to 75%. For a more detailed look at January weather in the region, you can visit this link: Koshi weather in January.
In December, temperatures range from a low of -2°C (29°F) to a high of 22°C (72°F), with an average temperature of 7°C (45°F). The month sees approximately 71 mm (2.8 in) of precipitation over about 7 days, and humidity levels are relatively high at 79%. In contrast, February experiences slightly colder temperatures, with minimums dropping to -5°C (24°F) and maximums reaching 20°C (69°F). The average temperature remains similar at 7°C (44°F), but February has increased precipitation at 96 mm (3.8 in) over 10 days, along with a lower humidity level of 71%. For more specific weather details, you can check Koshi weather in February.
December and March present distinct weather patterns. December typically experiences cooler temperatures, with a minimum of -2°C (29°F) and an average of 7°C (45°F), peaking at 22°C (72°F). Precipitation during this month amounts to 71 mm (2.8 in) over 7 days, accompanied by higher humidity at 79%. In contrast, March ushers in milder weather, featuring a slightly warmer minimum of -1°C (30°F) and an average of 11°C (52°F), with maximum temperatures reaching 24°C (75°F). Rainfall in March is more substantial, totaling 131 mm (5.2 in) across 12 days, while humidity decreases to 71%. For a closer look at how conditions evolve, check out Koshi weather in March.
December and April present distinctly different weather patterns. In December, temperatures range from a chilly minimum of -2°C (29°F) to a comfortable maximum of 22°C (72°F), with an average of 7°C (45°F). The month sees a moderate amount of precipitation at 71 mm (2.8 in) over about 7 days, accompanied by relatively high humidity at 79%. In contrast, April experiences a milder climate, with temperatures varying from a minimum of 1°C (34°F) to a maximum of 28°C (82°F) and an average of 15°C (59°F). The total rainfall increases to 132 mm (5.2 in) over 9 days, while humidity remains slightly lower at 78%. For more detailed information about April weather, you can check out Koshi weather in April.
In December, the weather is quite chilly, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 22°C (72°F), and an average temperature of 7°C (45°F). The month sees about 71 mm (2.8 in) of precipitation spread over 7 days, accompanied by a humidity level of 79%. In contrast, May brings much warmer conditions, with minimum temperatures starting at 6°C (43°F) and soaring to a maximum of 30°C (86°F), while the average temperature reaches a comfortable 19°C (67°F). However, May is also wetter, with total precipitation of 213 mm (8.4 in) over 12 days and slightly higher humidity at 84%. For more specific information about weather during this month in the Koshi area, check out Koshi weather in May.
In December, the weather tends to be quite cool, with temperatures ranging from a minimum of -2°C (29°F) to an average of 7°C (45°F) and a maximum of 22°C (72°F). This month typically sees about 71 mm (2.8 in) of precipitation over 7 days, and the humidity hovers around 79%. In stark contrast, June experiences much warmer temperatures, with a minimum of 13°C (55°F), an average of 23°C (73°F), and a maximum of 32°C (89°F). The precipitation also increases significantly, reaching 274 mm (10.8 in) over 15 days, coupled with a higher humidity level of 86%. For more detailed insights on Koshi weather during this month, you can visit Koshi weather in June.
December and July present strikingly different weather conditions. In December, temperatures range from a chilly -2°C (29°F) at night to a milder 22°C (72°F) during the day, with an average of 7°C (45°F). The month experiences about 71 mm (2.8 in) of precipitation across 7 days and features a humidity level of 79%. In contrast, July heats up significantly, with temperatures soaring from a minimum of 17°C (63°F) to a maximum of 35°C (96°F), averaging around 26°C (79°F). This month sees much heavier rainfall, totaling 478 mm (18.8 in) over 20 days, accompanied by high humidity levels of 92%. For more insights about July weather, you can check Koshi weather in July.
In December, the weather is considerably cooler, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 22°C (72°F), and an average temperature of 7°C (45°F). Precipitation is moderate at 71 mm (2.8 in) over about 7 days, accompanied by a humidity level of 79%. In contrast, August experiences much warmer conditions, with temperatures starting at a minimum of 18°C (65°F) and soaring up to 35°C (96°F), averaging around 28°C (82°F). This month also sees higher precipitation levels, totaling 277 mm (10.9 in) across 15 days, along with increased humidity at 91%. For more detailed information on August weather, check Koshi weather in August.
In December, temperatures are significantly cooler, with a minimum of -2°C (29°F) and an average of 7°C (45°F), peaking at 22°C (72°F). This month experiences moderate precipitation of 71 mm (2.8 in) over about 7 days, coupled with a humidity level of 79%. In contrast, September boasts much warmer conditions, with minimum temperatures starting at 12°C (53°F) and averaging around 24°C (76°F), reaching a high of 34°C (94°F). However, it is also wetter, recording 184 mm (7.2 in) of rain over approximately 14 days and a slightly higher humidity of 84%. For more detailed information about September weather, check out Koshi weather in September.
December's weather is notably cooler, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 22°C (72°F), offering an average of 7°C (45°F). It also sees around 71 mm (2.8 in) of precipitation over 7 days, and the humidity is relatively high at 79%. In contrast, October enjoys milder temperatures, starting at a minimum of 6°C (44°F) and reaching up to 31°C (88°F), with an average of 19°C (66°F). October experiences more rainfall, totaling 107 mm (4.2 in) across 8 days, and has a slightly higher humidity level at 83%. For more detailed information on the weather during October, you can refer to this link: Koshi weather in October.
In comparing the weather between November and December, we see a notable shift in temperature and precipitation patterns. November presents slightly milder temperatures, with an average of 12°C (55°F) and a maximum reaching 25°C (77°F), whereas December's temperatures drop with an average of 7°C (45°F) and a maximum of 22°C (72°F). Humidity levels remain relatively similar, at 81% in November and 79% in December, suggesting a dampness prevalent in both months. Precipitation is also slightly higher in December, with 71 mm (2.8 in) recorded compared to November's 60 mm (2.4 in), both spread across 7 days. For a detailed look at November's weather specifics, you can check out Koshi weather in November.
As December settles over Koshi, the weather experiences a notable shift, with temperatures taking a dip compared to the milder months preceding it. While highs reach a comfortable 22°C (72°F), the average cools to around 7°C (45°F), reminding residents and visitors alike that winter is on the horizon. The increase in humidity at 79% combined with 71 mm of precipitation over the month means those cozy indoor moments become even more appealing. With 7 rainy days, December's weather offers a contrasting backdrop to the vibrant seasons before, inviting a reflective pause as nature prepares for the colder months ahead. For more insights, explore Koshi Climate.