Last updated: August 21, 2025
December in Nagano, Japan brings a dramatic mix of winter weather, with temperatures ranging from a maximum of 19°C (66°F) to a chilly minimum of -10°C (14°F). The average temperature sits at a crisp 1°C (34°F), making it a time for warm layers and cozy activities. This month is characterized by frequent precipitation, averaging 151 mm (6.0 in) over 20 days, contributing to the region's stunning winter landscapes. With an humidity level of 86%, the air feels particularly brisk, enhancing the enchanting atmosphere that December brings to this beautiful part of Japan.
In Nagano, Japan, December ushers in the winter chill with temperatures that typically range from a brisk -10°C (14°F) at their lowest to a mild 19°C (66°F) at their peak. As the month progresses, the average temperature hovers around 1°C (34°F), providing a sharp contrast to the mild autumn just experienced. Compared to the preceding month of November, which shows a wider range of temperatures and slightly milder lows, December marks a significant drop as the region prepares for the snow-covered landscapes of winter. This distinct shift not only creates a picturesque winter wonderland but also signals a time for seasonal festivities and the exhilarating appeal of winter sports in the Japanese Alps.
In December, Nagano experiences an average precipitation of 151 mm (6.0 in), marking a notable increase compared to the preceding month, November, which recorded only 94 mm (3.7 in). This month typically sees precipitation on approximately 20 days, which reflects the onset of winter weather patterns in the region. The heightened precipitation levels are indicative of the seasonal transition, as December's moist atmosphere prepares for the heavier snowfalls characteristic of January and February. This trend underscores Nagano's distinctive climate, where late autumn gives way to a winter wonderland, enhancing the area's natural beauty and allure for winter sports enthusiasts.
In December, Nagano experiences a humidity level of 86%, slightly lower than the preceding month of November, which recorded 85%. This slight dip is part of a gradual decline from the peak summer months, where humidity surged to 92% in both July and August. The trend throughout the year shows that while winter months like December maintain a relatively high humidity, they are noticeably drier compared to the sweltering summer. Spring and early autumn also witness moderate humidity levels, hovering around the 80% mark, suggesting a comfortable transition as the seasons change. Overall, the humid climate of Nagano remains a defining characteristic, especially as the year wraps up in December, with moisture levels still significant enough to remind visitors of the region’s lush landscapes.
In December, Nagano experiences a moderate UV Index of 3, indicating a relatively low risk of harm from unprotected sun exposure, with a burn time of 30 minutes for fair-skinned individuals. This marks a gentle decline in UV intensity as the region transitions from the higher indices seen in the preceding summer months. Following the extreme conditions in May through August, where UV levels peaked at 11, December offers a welcome reprieve. As the year closes, sun safety remains important, but outdoor enthusiasts can enjoy the winter landscape with less concern for UV-related damage. For more detailed information, you can visit Nagano UV Index.
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December in Nagano, Japan, offers a modest 208 hours of sunshine, a slight dip from the preceding months. As the year draws to a close, the region enjoys a mix of crisp winter air and gentle rays, signaling the transition into colder seasons. Despite this decrease, December still boasts ample daylight compared to earlier winter months like January, which records the lowest with 174 hours. Notably, the sunshine peaks in the spring and summer months, reaching a high of 300 hours in May, creating a beautiful contrast to the winter months. This consistent sunlight trend showcases Nagano's charm throughout the year, from vibrant blossoms in spring to breathtaking snow scenes in winter.
In December, Nagano, Japan, experiences a 34% chance of sunny weather, slightly lower than the preceding month's 42%. This pattern reflects a trend where the transition from autumn to winter tends to bring a mix of conditions, with sunlight becoming less frequent as the region braces for colder temperatures and potential snowfall. While December does not boast the sunniest days of the year, its clear skies still hold the promise of pleasant winter sunlight on occasion, making it a charming time to enjoy the crisp air and scenic landscapes of Nagano.
In Nagano, Japan, the daylight duration exhibits a notable seasonal rhythm, reflecting the changing patterns of the year. As winter approaches, December sees daylight tapering back to 9 hours, mirroring the 9 hours of light experienced in January. This brief daylight period marks the culmination of a gradual decline that starts after the peak of 14 hours in the vibrant summer months of June through August. As the year transitions from the warmth of spring into the cooler embrace of winter, daylight steadily diminishes from 14 hours in May down to 10 hours by November. This cyclical shift not only emphasizes the beauty of each season but also invites residents and visitors alike to embrace the cozy, reflective atmosphere that Nagano offers during the shorter days of December.
As December arrives in Nagano, Japan, the wind begins to whisper its cool secrets, averaging 1.8 m/s (4 mph) this month. While December's breeze may seem reminiscent of the calmer winds from earlier months, a subtle trend emerges as the year progresses; the wind speed gradually increases from the softness of summer, peaking slightly in the springtime. The quiet stillness of July and August, marked by gentle 1.3 m/s (3 mph) winds, gives way to the crisp breezes that herald winter. December's air may carry a refreshing chill, but it remains mild compared to the gusts of March and April, which hint at the awakening of spring. This tapestry of changing winds not only highlights the seasonal shifts but enhances the serene beauty of Nagano's winter landscape, inviting residents and visitors alike to embrace the season's delicate charm.
Weather in Nagano varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Nagano, focusing on differences in temperature, rainfall, humidity, and UV levels.
December and January both showcase the chilly winter climate, yet there are notable differences between the two months. In December, temperatures range from a minimum of -10°C (14°F) to a maximum of 19°C (66°F), averaging around 1°C (34°F). The month sees approximately 151 mm (6.0 in) of precipitation over 20 days, with a humidity level of 86%.
In contrast, January is colder, with temperatures dipping as low as -15°C (6°F) and peaking at 10°C (51°F), averaging -2°C (29°F). This month has slightly less precipitation at 144 mm (5.7 in), occurring on 21 days, and a marginally higher humidity of 88%. For more detailed insights, you can check out Nagano weather in January.
December and February in Nagano showcase distinct winter characteristics, particularly in temperature and precipitation. December experiences a milder average temperature of 1°C (34°F), with maximums reaching up to 19°C (66°F), while February is colder, with an average of -1°C (30°F) and a minimum of -14°C (7°F). Both months present a similar level of humidity at 86%, contributing to a consistent winter atmosphere. Precipitation is also prevalent; December sees 151 mm (6.0 in) over 20 days, whereas February has slightly lower precipitation at 129 mm (5.1 in) across 19 days. For more details on February weather, you can check Nagano weather in February.
In comparing the weather between December and March, we see notable differences in temperature and precipitation. December typically experiences colder conditions, with an average temperature around 1°C (34°F), while March warms up slightly, averaging 4°C (39°F). The maximum temperatures also rise from 19°C (66°F) in December to 21°C (70°F) in March. Precipitation levels are relatively similar, with December receiving 151 mm (6.0 in) over 20 days, compared to March's 133 mm (5.2 in) spread over 18 days. Additionally, humidity is slightly higher in December at 86%, compared to 81% in March. For more details on March weather in Nagano, you can visit Nagano weather in March.
In December, temperatures in Nagano can plummet to a minimum of -10°C (14°F), with an average around 1°C (34°F) and a maximum reaching 19°C (66°F). The month is characterized by high humidity at 86% and substantial precipitation of 151 mm (6.0 in) over approximately 20 days. In stark contrast, April sees a noticeable warming trend, with temperatures starting at a low of -5°C (22°F), averaging 9°C (48°F), and peaking at 27°C (81°F). Although it experiences slightly less rainfall at 141 mm (5.5 in), precipitation occurs over 16 days and humidity drops to 78%. For more details on the weather trends, you can check Nagano weather in April.
December and May present contrasting weather conditions. In December, temperatures can plunge as low as -10°C (14°F) at night, with an average daytime high of just 1°C (34°F), while precipitation is frequent, occurring on about 20 days, leading to a humidity level of 86%. In stark contrast, May brings milder temperatures, with nighttime lows of around 0°C (33°F) and average highs reaching 15°C (59°F). Although May experiences slightly more precipitation at 160 mm (6.3 in) over 16 days, the overall humidity is lower at 81%. For more details on May weather specifics, you can check out Nagano weather in May.
December and June present contrasting weather patterns. In December, temperatures can dive as low as -10°C (14°F), averaging around 1°C (34°F) during the day, with a maximum of 19°C (66°F). This month sees significant precipitation, totaling 151 mm (6.0 in) over approximately 20 days, accompanied by high humidity at 86%. In comparison, June enjoys milder temperatures, with a minimum of 5°C (41°F) and an average of 18°C (65°F), reaching up to a maximum of 30°C (87°F). Although June experiences slightly more precipitation at 171 mm (6.7 in) over 18 days, the humidity rises only slightly to 88%. For more detailed information about June weather, check out Nagano weather in June.
December and July present starkly contrasting weather patterns. In December, temperatures can dip as low as -10°C (14°F) and typically hover around an average of 1°C (34°F), with a maximum of 19°C (66°F). The month experiences considerable precipitation, with around 151 mm (6.0 in) falling over 20 days, accompanied by high humidity levels at 86%. In contrast, July boasts a milder climate, with minimum temperatures rising to 15°C (60°F) and averages hitting 22°C (73°F), peaking at 33°C (91°F). This month sees even higher rainfall, accumulating to 341 mm (13.4 in) over 25 days, and slightly increased humidity at 92%. For more specifics on the warm July conditions, you can explore Nagano weather in July.
The weather in December contrasts sharply with that of August. In December, temperatures range from a frigid minimum of -10°C (14°F) to a mild maximum of 19°C (66°F), resulting in an average of just 1°C (34°F). The month experiences significant precipitation, totaling 151 mm (6.0 in) over about 20 days, with humidity levels around 86%. In stark contrast, August boasts much warmer temperatures, with a minimum of 11°C (52°F), an average of 24°C (75°F), and a scorching maximum of 35°C (95°F). While August also sees frequent rain, with precipitation reaching 198 mm (7.8 in) over 23 days, the humidity is slightly higher at 92%. This stark difference in temperature and weather patterns highlights the seasonal variations typical of the region. For more details about the August climate, you can visit Nagano weather in August.
In December, the weather shifts to much colder temperatures, with a minimum of -10°C (14°F) and an average of 1°C (34°F), while the maximum reaches only 19°C (66°F). This period is characterized by significant precipitation totaling 151 mm (6.0 in) over 20 days, along with high humidity at 86%. In contrast, September brings a much warmer climate, with temperatures ranging from a minimum of 7°C (44°F) to an average of 19°C (67°F) and highs peaking at 32°C (89°F). Despite receiving slightly more rainfall of 194 mm (7.6 in) over 19 days, September's humidity remains comparable at 89%. For more details on September weather, check out Nagano weather in September.
December weather contrasts sharply with that of October. While December experiences colder temperatures, with a minimum of -10°C (14°F) and an average of 1°C (34°F), October showcases much milder conditions, ranging from a minimum of 2°C (36°F) to a maximum of 28°C (82°F) and an average of 13°C (56°F). Additionally, October has a higher rainfall total of 217 mm (8.5 in) over 18 days, compared to December's 151 mm (6.0 in) over 20 days, indicating more consistent precipitation earlier in the fall. Humidity levels remain similar, hovering around 86% in December and 87% in October. For a closer look at what to expect during this autumn month, check out Nagano weather in October.
December weather is marked by colder temperatures compared to November, with minimums dropping to -10°C (14°F) and an average of just 1°C (34°F). In contrast, November sees milder temps, with a minimum of -8°C (19°F) and a more comfortable average of 7°C (44°F). Additionally, December experiences significantly higher precipitation at 151 mm (6.0 in) over 20 days, compared to November's 94 mm (3.7 in) over 15 days. Humidity levels remain quite similar, with December at 86% and November at 85%. For more insights into November's weather, visit Nagano weather in November.
As December settles in Nagano, the weather transforms dramatically, bringing a chilly charm that sets it apart from other months. With average temperatures dipping to a brisk 1°C and nights plunging as low as -10°C, the month is marked by cold winds and an inviting blanket of snow, signifying the start of winter activities. Contrary to the milder conditions of previous months, December experiences heightened precipitation, with about 20 days of rain and snow, leading to an atmospheric humidity of 86%. This unique blend of cold and moisture creates a picturesque winter landscape, perfect for those looking to embrace the season. For a deeper dive into Nagano's weather patterns, visit the comprehensive Nagano Climate page.