Last updated: August 21, 2025
In Hachioji during December, the weather presents a vivid contrast, with maximum temperatures reaching 20°C (69°F), while averages settle around a brisk 5°C (42°F) and minima dipping to a chilly -5°C (23°F). Tourists and residents alike might experience a mix of conditions, as the city sees about 62 mm (2.4 in) of precipitation over approximately 9 days. With humidity levels lingering at 78%, December in Hachioji is a month of refreshing coolness, perfect for enjoying seasonal festivities and the beauty of winter landscapes.
In Hachioji, Japan, December marks a transition into the colder months, with temperatures dipping noticeably. With a minimum of -5°C (23°F) and an average around 5°C (42°F), residents begin to feel the chill as winter approaches. The maximum temperature can still reach up to 20°C (69°F), hinting at some unseasonably warm days amidst the cooling trend. Compared to the milder temperatures of November, where the average was 11°C (52°F), December brings a sharper decline, marked by crisper air and shorter days. This shift lays the groundwork for the deep winter months, showcasing Hachioji's diverse climate as it transitions from autumn's lingering warmth to the frigid embrace of January.
In Hachioji, Japan, December brings a slight decrease in precipitation, with an average of 62 mm (2.4 in) over just 9 days. This month's rainfall is modest compared to the warmer months, especially when juxtaposed with the heavy showers of July, which often exceed 300 mm. Notably, December's precipitation mirrors February’s amounts, indicating a seasonal pattern where late autumn transitions into a milder winter. As the year wraps up, the consistent rainfall from earlier months gives way to drier conditions, allowing the landscape to prepare for the cold ahead. This trend of fluctuating moisture underscores Hachioji's diverse climate, influenced heavily by shifting seasons.
As December unfolds in Hachioji, Japan, the city experiences a moderate humidity level of 78%, which is indicative of the seasonal transition toward winter. This reading marks a slight decrease from the humidity peak during the summer months, where values soared to 93% in July. Interestingly, the fall months exhibit a gradual decline from 80% in November to December's 78%, suggesting a trend of diminishing moisture as the year progresses toward its close. Overall, while December's humidity remains relatively high compared to the year's early months—where averages hover around 70-76%—it signals a return to the crispness of winter, paving the way for colder, drier days ahead.
As December settles in Hachioji, Japan, locals experience a moderate UV Index of 4, similar to the beginning of the year in January. This winter month allows for leisurely outdoor activities with a relatively safe burn time of 30 minutes before sun damage becomes a concern. Reflecting on the year’s trends, the UV Index peaks during the summer months, reaching an extreme level of 11 from May through August, while the spring months show a sharp increase in UV radiation intensity. The gradual decrease from early summer to winter illustrates a significant seasonal pattern, reminding us to stay vigilant even in the cooler months. For more insights on UV levels throughout the year, check out the detailed Hachioji UV Index.
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In Hachioji, Japan, December brings a comforting 233 hours of sunshine, marking a gentle decline from the sunnier heights of late summer. Following a peak of 284 hours in August, the month sees the daylight hours gradually wane through the fall, yet it still outshines January's dreary start with its modest brightness. Interestingly, the sunshine levels of December are reminiscent of November's 231 hours, illustrating a stable transition into winter. As the year ends, residents can relish the crisp air alongside a generous share of daylight, offering a cheerful backdrop to festive celebrations and reflective moments as the year draws to a close.
In Hachioji, Japan, the likelihood of enjoying sunny weather in December stands at a promising 68%, making it one of the more favorable months for sunshine. This percentage shows a notable increase following November's 56%, hinting at a positive trend as the year wraps up. While the colder months generally see a dip in sunny days, December bucks this trend with a higher chance of clear skies compared to the transitional months of April (45%) and October (46%). As we reflect on the data, it becomes clear that December is a month to savor sunny moments amidst the chill, providing a bright close to the year.
As December unfolds in Hachioji, Japan, the daylight hours dip to nine—the shortest span of the year. This gradual decrease follows a pattern established from the summer months, where daylight peaks at 14 hours in June and July, then steadily wanes as autumn arrives. From 14 hours in May to 10 hours in November, the sun's presence diminishes, leading to the cozy, shorter days of winter. While the chill of December settles in, the light retreats, inviting a sense of reflection and warmth as the year comes to a close.
As December arrives in Hachioji, Japan, the average wind speed settles at 2.0 m/s (4 mph), mirroring the calmer breezes of October and November. This marks a subtle shift from the warmer months, where July and August experienced the lowest winds of the year, with speeds dipping to 1.5 m/s (3 mph). Transitioning from late autumn to early winter, the winds pick up slightly, reflecting the season’s crispness and setting a serene yet invigorating atmosphere. Interestingly, December's winds echo the consistent, gentle breezes of early months like March and April, where the average speed hovers around 2.3 m/s (5 mph), highlighting a seasonal rhythm where tranquility prevails, inviting residents and visitors alike to relish the beauty of Hachioji's winter landscape.
Weather in Hachioji varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Hachioji, focusing on differences in temperature, rainfall, humidity, and UV levels.
December and January exhibit notable differences in weather. December experiences a wider temperature range, with minimums around -5°C (23°F) and maximums reaching up to 20°C (69°F), resulting in an average temperature of 5°C (42°F). This month also sees about 62 mm (2.4 in) of precipitation over 9 days, with relative humidity at 78%. In contrast, January is characterized by colder temperatures, marked by lower minimums of -13°C (9°F) and an average of 3°C (37°F), while the maximum remains cooler at 17°C (63°F). This month brings slightly less precipitation, with 53 mm (2.1 in) over 7 days and a marginally lower humidity of 76%. For more details on January weather, you can visit Hachioji weather in January.
In December, the weather typically features a minimum temperature of -5°C (23°F) and an average of 5°C (42°F), peaking at a maximum of 20°C (69°F). This month experiences about 62 mm (2.4 in) of precipitation over 9 days, with humidity levels averaging around 78%.
Conversely, February sees slightly colder conditions, with a minimum of -6°C (21°F) and an average temperature of 4°C (40°F), reaching a maximum of 21°C (69°F). Precipitation remains consistent at 62 mm (2.4 in) but is spread over 10 days, and humidity drops to an average of 74%.
For more detailed insights, you can explore Hachioji weather in February.
December and March present contrasting weather patterns. In December, temperatures range from a chilly minimum of -5°C (23°F) to an average of 5°C (42°F) and can peak at 20°C (69°F). The month sees a moderate amount of precipitation at 62 mm (2.4 in) over about 9 days, with a higher humidity level of 78%. In contrast, March experiences slightly milder temperatures with a minimum of -4°C (26°F) and an average of 8°C (47°F), reaching up to 23°C (73°F) at its peak. However, it is marked by significantly increased rainfall at 166 mm (6.5 in) over 14 days, albeit with lower humidity at 70%. For more detailed information on March weather, you can check Hachioji weather in March.
In December, the weather tends to be quite chilly, with minimum temperatures dropping to -5°C (23°F) and average highs around 5°C (42°F), while occasionally peaking at a maximum of 20°C (69°F). The month sees relatively low precipitation, totaling 62 mm (2.4 in) over about 9 days, and maintains a humidity level of 78%.
In contrast, April brings a significant warming trend, featuring minimum temperatures around -2°C (29°F) and an average temperature soaring to 12°C (54°F), with maximums reaching a pleasant 26°C (79°F). However, it is also a wetter month, with precipitation increasing to 150 mm (5.9 in) over approximately 15 days and slightly lower humidity at 74%. For a detailed look at conditions, you can visit Hachioji weather in April.
December and May present contrasting weather conditions. In December, temperatures range from a chilly minimum of -5°C (23°F) to a comfortable maximum of 20°C (69°F), with an average of 5°C (42°F). The month experiences about 62 mm (2.4 in) of precipitation over 9 days, accompanied by a humidity level of 78%. In stark contrast, May sees much higher temperatures with a minimum of 4°C (39°F), an average of 17°C (64°F), and a peak of 30°C (86°F). Rainfall is more frequent in May, with 148 mm (5.8 in) expected over 15 days and slightly higher humidity at 81%. For more details on May weather, check out Hachioji weather in May.
In December, Hachioji experiences a cooler climate with temperatures ranging from a minimum of -5°C (23°F) to a maximum of 20°C (69°F), averaging around 5°C (42°F). The month sees moderate precipitation of 62 mm (2.4 in) over about 9 days, with a humidity level of 78%. In contrast, June offers a significantly warmer atmosphere, with temperatures fluctuating between a minimum of 11°C (52°F) and a maximum of 31°C (88°F), resulting in an average temperature of 20°C (69°F). This month is much wetter, receiving 209 mm (8.2 in) of rain over 19 days, and it also has higher humidity at 88%. For a closer look at Hachioji's June weather, visit Hachioji weather in June.
In December, temperatures range significantly, with minimums dipping to -5°C (23°F) and averaging around 5°C (42°F), while maximums can reach up to 20°C (69°F). The month also sees a moderate level of precipitation at 62 mm (2.4 in) over about 9 days, accompanied by relatively high humidity levels at 78%. In stark contrast, July experiences warm and humid conditions, with a minimum temperature of 16°C (60°F) and an average high of 24°C (76°F), soaring to a maximum of 35°C (95°F). July is notably wetter, accumulating 312 mm (12.3 in) of rainfall over 24 days, complemented by even higher humidity at 93%. For more details on July weather, visit Hachioji weather in July.
December and August present stark contrasts in weather. In December, temperatures range from a chilly minimum of -5°C (23°F) to a mild maximum of 20°C (69°F), with an average temperature of around 5°C (42°F). The month experiences about 62 mm (2.4 in) of precipitation over 9 days, accompanied by a relatively high humidity of 78%. In contrast, August boasts much warmer conditions, with temperatures ranging from a minimum of 15°C (59°F) to a scorching maximum of 36°C (97°F), with an average of 26°C (79°F). It is also the wettest month, with 195 mm (7.7 in) of precipitation over 23 days and even higher humidity at 90%. For a detailed look at August weather, visit Hachioji weather in August.
When comparing the weather in December to that of September, it's clear that the two months present starkly different climates. December features significantly cooler temperatures, with lows plunging to -5°C (23°F) and an average of just 5°C (42°F), while September boasts much warmer conditions, starting with a minimum of 12°C (53°F) and averaging 22°C (71°F). In terms of precipitation, December experiences 62 mm (2.4 in) over 9 days, compared to a much wetter September, which sees 247 mm (9.7 in) over 22 days. Additionally, September has a higher humidity level of 86%, compared to December's 78%, making the latter month feel somewhat drier despite the chill. For more detailed insights into September's weather, you can check Hachioji weather in September.
In comparing December and October weather, it's evident that October is significantly warmer, with average temperatures reaching 16°C (61°F), whereas December's average drops to a cooler 5°C (42°F). The peak temperatures in October can soar up to 30°C (86°F), while December's maximum stands at a modest 20°C (69°F). Additionally, October experiences much higher precipitation levels, totaling 346 mm (13.6 in) over 19 days, compared to December’s 62 mm (2.4 in) spread across 9 days. October also has a slightly higher humidity level at 83%, compared to December's 78%. For more details, you can check Hachioji weather in October.
In comparing the weather between November and December, we see a notable shift in temperatures and precipitation. December experiences cooler temperatures, with an average of 5°C (42°F), while November begins with a milder average of 11°C (52°F). The maximum temperature in December reaches 20°C (69°F), slightly lower compared to November's high of 23°C (73°F). In terms of precipitation, December records 62 mm (2.4 in) over 9 days, while November sees a bit more rain with 72 mm (2.8 in) spread across 10 days. Additionally, humidity levels remain quite similar, with December at 78% and November slightly higher at 80%. For more detailed information on November weather, check Hachioji weather in November.
As December approaches in Hachioji, the weather undergoes a noticeable shift compared to the milder months of autumn. The maximum temperatures drop significantly, hovering around a comfortable yet cool 5°C, while minimums can plunge to as low as -5°C. This month also sees an increase in precipitation, with around 62 mm falling over approximately 9 days; thus, it becomes one of the wetter months of the year. Additionally, with humidity levels rising to 78%, the air feels quite different, adding to the crispness of the winter season. For those looking to explore more about the year's climate, check out Hachioji Climate.