December Weather in Muroran, Japan

Last updated: August 21, 2025

In Muroran, Japan, December ushers in chilly temperatures, with a maximum of 13°C (56°F) and an average hovering around 1°C (35°F), dipping to a minimum of -6°C (21°F). The month is characterized by significant precipitation, totaling 86 mm (3.4 in) over 21 days, leading to a humid environment with an average humidity of 80%. As the year draws to a close, residents and visitors alike experience a blend of wintry conditions, making December a month to prepare for cold adventures as the landscape transforms under occasional snowfall.

December Temperature in Muroran

As December sets in, Muroran, Japan, experiences a notable shift in temperatures, with crisp, chilly days marking the onset of winter. The month kicks off with minimums dropping to -6°C (21°F) and average temperatures lingering around 1°C (35°F), making it one of the colder months of the year. While the maximum temperature reaches a mild 13°C (56°F), suggesting occasional warmer spells, the overall climate remains decidedly brisk. This trend towards lower temperatures is consistent with the gradual decline observed from November's more moderate averages, highlighting the deepening chill as Muroran steps further into winter. Wrapped in its frosty embrace, December invites residents and visitors alike to enjoy the serene beauty of the season, even as they bundle up against the cold.

December Weather in Muroran: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Muroran, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Muroran, December typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec303036425058667066574634
Data source: Temperature data for Muroran generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Muroran

December in Muroran, Japan, ushers in a notable increase in precipitation, with an average of 86 mm (3.4 in) falling over the month. This quantity is consistent with the wet conditions typical of late autumn, yet it surprises with a substantial 21 days of rainfall, the highest of any month this season. While precipitation begins to taper off in the ensuing winter months, December's combination of moderate rainfall and frequent rainy days paints a vivid picture of the city’s transition into winter. Such patterns not only highlight a rainy close to the year but also set the stage for the potential snowfall that Muroran experiences in January and February.

December Precipitation Trends in Muroran

The chart displays monthly precipitation patterns in Muroran, with values for each month alongside December’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December’s conditions compare to those of other months. In Muroran, December typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec66598186991261281941371279586
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Muroran

In December, Muroran, Japan, experiences a notable shift in humidity, settling at a comfortable 80%. This marks a decrease from the climactic highs of July and August, where humidity peaks at 93% and 95%, respectively. Following a steady decline from the fall months—where November registers at 79%—December offers a refreshing respite, reminiscent of the milder conditions seen in April and March, both at 81%. As the year draws to a close, the relatively stable humidity levels reflect the city's transition from the warm, sultry summer months to the cool embrace of winter, creating a cozy atmosphere throughout the season.

December Average Humidity in Muroran

This chart illustrates the average monthly humidity levels in Muroran, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Muroran is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec85%83%81%81%86%87%93%95%88%83%79%80%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Muroran

In December, Muroran, Japan experiences a significant drop in UV exposure, registering a UV Index of 2, which falls into the low exposure category. This decrease follows a series of months with heightened UV levels, peaking at 10 in both June and August, indicating the summer's intense sun. With a burn time of 45 minutes, residents and visitors alike can enjoy the outdoors more comfortably without the immediate concern of sunburn, unlike in the peak summer months where burn times plummeted to just 15 minutes. As the year wraps up, December's low index marks a gentle transition towards winter, contrasting sharply with the intense UV rays of spring and summer. For more detailed insights, explore the complete Muroran UV Index.

Maximum UV Index Levels in Muroran for December

The chart shows the monthly maximum UV Index (UVI) for Muroran in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In December, the maximum UV index in Muroran typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec23579109108632
Data source: Muroran December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

December Sunshine in Muroran

In Muroran, Japan, December marks a subtle shift in daylight as the year draws to a close, offering around 170 hours of sunshine. While this figure reflects a noticeable decrease from the vibrant hours of spring and summer, which bask in more than 285 hours of sunlight, December’s light still provides a warm backdrop to the winter season. Interestingly, the sunshine trend for the year reveals a gradual buildup from a modest 142 hours in January, reaching a peak in May. As the seasons transition, the hours dip progressively, hinting at nature's cyclical rhythm. Yet, even in December, the gentle glow of daylight encourages reflection and preparation for the brighter days ahead.

Monthly Sunshine Duration in Muroran: December Highlighted

The December sunshine duration represents the total number of hours Muroran experiences direct sunlight during the month of December, excluding cloudy or obstructed periods. This chart compares the sunshine duration of December with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec142h195h253h285h300h294h299h277h265h235h183h170h
Data source: Muroran December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Muroran During December

In Muroran, Japan, the likelihood of sunny weather in December stands at 34%, which is slightly lower than the average for the preceding months. As the year progresses, we see a notable increase in sunshine probabilities during the spring months, peaking at 45% in April. However, the summer months fall short, with only 28% in July and an even lower 24% in August, leading to a gradual recovery come autumn as November brings 42% sunshine. December's 34% chance aligns closely with its winter peers, suggesting that while the season winds down, there's still a fair opportunity to enjoy some clear skies amidst the cooler temperatures.

Percentage of Sunny Days in December in Muroran

The chart illustrates the percentage of sunny days in Muroran throughout the year, with December highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Muroran experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec32%34%37%45%31%43%28%24%40%43%42%34%
Data source: Muroran December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Muroran in December

In Muroran, Japan, the transition from autumn to winter brings a noticeable shift in daylight duration. December, with its 9 hours of daylight, mirrors both January and November, marking the shortest days of the year. This slight dip is part of a broader trend, as daylight steadily increases from 10 hours in February to a peak of 15 hours in June during the vibrant summer months. The gradual increase begins again in March, highlighting the changing seasons as nature awakens. Ultimately, the pattern reflects the rhythmic dance of the seasons, showcasing the balance of light and darkness that characterizes life in this picturesque coastal town.

Average Daylight Hours in Muroran for December

The chart illustrates the variation in daylight duration in Muroran throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 27m10h 32m11h 56m13h 22m14h 35m15h 12m14h 53m13h 49m12h 27m11h 2m9h 46m9h 7m
Data source: Muroran daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Muroran

As December welcomes cooler temperatures in Muroran, Japan, the average wind speed picks up slightly to 6.7 m/s (15 mph), a noticeable rise from November's 6.4 m/s (14 mph). The trend of increasing winds toward the end of the year contrasts with the calmer conditions experienced during the summer months, where speeds dipped to as low as 3.9 m/s (9 mph) in June. This gradual escalation in wind intensity not only reflects the changing seasons but also sets the stage for the crisp, invigorating breezes that characterize the winter months in this coastal city. The shift in wind patterns emphasizes the dynamic climate of Muroran, where each month's narrative unfolds through the lens of its ever-changing breezes.

Average December Wind Speed in Muroran

The chart displays monthly wind speed patterns in Muroran, with values for each month shown alongside December's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how December's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec7.07.14.84.84.33.94.35.24.24.86.46.7 m/s
Data source: Muroran December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Muroran Compares to Other Months

Weather in Muroran varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Muroran, focusing on differences in temperature, rainfall, humidity, and UV levels.

December and January showcase notable differences in weather patterns. In December, temperatures range from a minimum of -6°C (21°F) to a maximum of 13°C (56°F), with an average temperature of 1°C (35°F). The month experiences significant precipitation, totaling 86 mm (3.4 in) over 21 days, while humidity remains relatively high at 80%. Conversely, January sees a drop in temperatures, with minimums reaching -9°C (16°F) and a maximum of just 8°C (47°F), resulting in an average temperature of -1°C (30°F). Precipitation decreases to 66 mm (2.6 in), spread over 13 days, and humidity slightly rises to 84%. For a more detailed look at January weather, visit Muroran weather in January.

December and February each present distinct winter weather patterns. In December, temperatures range from a minimum of -6°C (21°F) to a maximum of 13°C (56°F), with an average of 1°C (35°F). This month receives a considerable amount of precipitation, totaling 86 mm (3.4 in) over 21 days, and maintains a high humidity level of 80%. In contrast, February tends to be colder, with temperatures dipping further to a minimum of -10°C (14°F) and an average of -1°C (30°F), peaking at 6°C (43°F). Precipitation in February decreases to 59 mm (2.3 in) over only 13 days, accompanied by a marginally higher humidity of 83%. For a closer look at February weather trends, visit Muroran weather in February.

In December, the weather tends to be colder, with temperatures ranging from a minimum of -6°C (21°F) to a maximum of 13°C (56°F) and an average of 1°C (35°F). The month sees significant precipitation, totaling 86 mm (3.4 in) over 21 days, contributing to an overall humidity level of 80%. In contrast, March offers slightly milder temperatures, with a minimum of -5°C (23°F) and a maximum of 10°C (50°F), resulting in an average of 2°C (36°F). Precipitation levels are only slightly lower at 81 mm (3.2 in), but this rain occurs over just 9 days, maintaining a similar humidity at 81%. For more detailed insights on weather conditions during this month, you can check Muroran weather in March.

In December, the weather is notably colder, with temperatures ranging from a minimum of -6°C (21°F) to a maximum of 13°C (56°F) and an average of around 1°C (35°F). The month is characterized by higher precipitation, occurring on about 21 days, resulting in a relatively gloomy atmosphere with 80% humidity. In contrast, April brings milder temperatures, with a minimum of 0°C (32°F) and a maximum of 15°C (59°F), averaging 6°C (42°F). While both months see the same total precipitation of 86 mm (3.4 in), April enjoys sunnier days, with rain falling over just 11 days, and only slightly higher humidity at 81%. For more details on the weather in April, visit Muroran weather in April.

In December, temperatures can drop as low as -6°C (21°F), with an average around 1°C (35°F) and highs reaching up to 13°C (56°F). The month is characterized by significant precipitation, totaling 86 mm (3.4 in) over about 21 days, coupled with a humidity level of 80%. In contrast, May brings milder weather, where temperatures start at a minimum of 5°C (41°F), with an average of 10°C (50°F) and can rise to a maximum of 22°C (73°F). Although precipitation increases slightly to 99 mm (3.9 in), it occurs over just 10 days, and humidity is slightly elevated at 86%. For more detailed insights, you can check out Muroran weather in May.

December and June present contrasting weather conditions. In December, temperatures can drop as low as -6°C (21°F), with an average of 1°C (35°F) and highs reaching up to 13°C (56°F). The month is characterized by significant precipitation, totaling 86 mm (3.4 in) over 21 days, and humidity levels are around 80%. In contrast, June offers a milder climate, with minimum temperatures of 9°C (48°F) and averages around 14°C (58°F), peaking at 20°C (69°F). Although June experiences more precipitation at 126 mm (5.0 in), it is spread over just 11 days, and humidity rises slightly to 87%. This shift from cold and snowy in December to warmer, more humid conditions in June highlights the diverse climate of the region. For more details on June weather, you can check Muroran weather in June.

December and July offer strikingly different weather conditions. In December, temperatures hover between a chilly -6°C (21°F) and a mild high of 13°C (56°F), with an average of just 1°C (35°F). This month sees significant precipitation, totaling 86 mm (3.4 in) over 21 days, and humidity remains relatively high at 80%. In contrast, July brings much warmer weather, with temperatures ranging from a minimum of 13°C (55°F) to a comfortable maximum of 26°C (79°F), averaging 19°C (66°F). Although July experiences even more total rainfall at 128 mm (5.0 in), it falls across just 14 days, and humidity rises slightly to 93%. For a closer look at July's conditions, you can check out Muroran weather in July.

December and August present stark contrasts in weather conditions. In December, temperatures range from a chilly -6°C (21°F) at night to a mild 13°C (56°F) during the day, with an average of 1°C (35°F). This month also experiences considerable precipitation, totaling 86 mm (3.4 in) over 21 days, and humidity levels hover around 80%. In contrast, August brings warmth with temperatures ranging from a minimum of 16°C (61°F) to a maximum of 27°C (82°F), averaging 21°C (70°F). Rainfall is more substantial during this month, with a total of 194 mm (7.7 in) spread over 15 days, and the humidity reaches a peak of 95%. For those curious about the specifics of weather in this summer month, additional details can be found at Muroran weather in August.

In December, the weather in Muroran is significantly colder, with average temperatures lingering around 1°C (35°F) and minimums dropping to as low as -6°C (21°F). In contrast, September boasts much milder conditions, with average temperatures reaching 19°C (67°F) and highs of 27°C (81°F). While December experiences approximately 86 mm (3.4 in) of precipitation over 21 days, September sees higher rainfall at 137 mm (5.4 in) over just 13 days. Humidity remains relatively high in both months, with December at 80% and September slightly higher at 88%. For a detailed look at September weather, visit Muroran weather in September.

When comparing December and October weather, there's a noticeable shift in temperature and precipitation patterns. In December, temperatures range from a chilly minimum of -6°C (21°F) to an average of 1°C (35°F) and a maximum of 13°C (56°F), contributing to a much colder atmosphere. In contrast, October enjoys milder weather with minimum temperatures around 6°C (43°F) and averages reaching up to 14°C (58°F), culminating at a warm maximum of 23°C (73°F). Additionally, December experiences more rainy days, with 86 mm (3.4 in) of precipitation spread over 21 days, while October, despite having higher total precipitation at 127 mm (5.0 in), sees it over a shorter period of just 12 days. Humidity levels are relatively close, hovering around 80% for December and 83% for October, but the overall feel is significantly different between the two months. For more details on October weather, you can check Muroran weather in October.

In comparing the weather between November and December, we observe notable changes. December typically sees colder temperatures, with a minimum of -6°C (21°F) and an average of 1°C (35°F), compared to November's milder lows of -3°C (28°F) and an average of 8°C (46°F). Precipitation remains relatively high in both months, with December recording 86 mm (3.4 in) over 21 days, while November has slightly more precipitation at 95 mm (3.8 in) across just 13 days. Humidity levels are similar, with December at 80% and November at 79%. For more detailed insights into November weather patterns, you can visit Muroran weather in November.

Compare Muroran's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Muroran

As December unfolds in Muroran, the weather showcases a distinct transition from the milder autumn months to the colder embrace of winter. With temperatures averaging around freezing and frequent precipitation, this month sets itself apart with higher humidity levels and a notable increase in rainy days. Unlike the more stable conditions of previous months, December can feel brisk and damp, requiring a more cozy wardrobe as residents and visitors prepare for the chill. The striking contrast between day and night temperatures adds an additional layer of winter character. For a deeper dive into Muroran's climate and how it evolves throughout the year, check out Muroran Climate.