Last updated: August 21, 2025
In Iwakuni, Japan, December reveals a blend of cool and crisp weather, with average temperatures hovering around 7°C (46°F). The month enjoys a maximum of 20°C (69°F) and can dip down to a chilling -1°C (31°F) at night. Visitors can expect moderate precipitation totaling 61 mm (2.4 in) over approximately 6 days, often accompanied by humidity levels averaging 75%. This combination creates a refreshing atmosphere, perfect for exploring the city's winter charm while staying prepared for the occasional drizzle.
In Iwakuni, Japan, December ushers in a noticeable drop in temperatures, signaling the approach of winter. With minimums hovering around -1°C (31°F) and averages settling at 7°C (46°F), the month paints a cooler picture compared to the milder conditions of late autumn. Daytime highs can still reach a comfortable 20°C (69°F), offering a brief respite from the chill, especially during sunny spells. This transition reflects a broader climatic trend, as Iwakuni moves from the moderate warmth of fall into the colder embrace of winter, a time where bundled-up strolls and cozy indoor activities become the norm.
December in Iwakuni, Japan, typically experiences 61 mm (2.4 in) of precipitation over 6 days, marking a slight increase from November's drier conditions. This early winter month showcases a transition as rainfall moderately resumes after the lighter fall months, contributing to the region's overall winter climate. December's precipitation is noticeably lower than the summer peak in July, which sees a staggering 386 mm (15.2 in), but aligns with the trend of increased rainfall from late autumn to early spring. Despite fewer rainfall days compared to the wetter months of June and July, December provides a refreshing dip into the rainy season, preparing Iwakuni’s landscape for the colder months ahead.
As the year draws to a close, December in Iwakuni, Japan, sees humidity levels at a comfortable 75%. This marks a slight decrease from the high of 88% in June and peaks of 95% in July, which characterize the summer months. The transition into winter brings a notable dip in humidity after the sweltering seasons, with levels steadily declining from a spring average of 75% and a higher 84% in May. Interestingly, December aligns closely with November’s 76%, indicating a stable air quality as the region shifts towards cooler temperatures. Overall, the latter part of the year showcases a pattern of fluctuating humidity, with the summer months significantly raising the average, contrasted by the drier, more temperate winter.
In December, Iwakuni experiences a moderate UV Index of 4, allowing for relatively safer sun exposure with a burn time of 30 minutes. This marks a noticeable shift from the extreme levels seen in the summer months, where values spiked to 12 in both July and August. As the year winds down, the trend moves towards safer UV conditions, with January also starting off at a moderate level of 4. This pattern highlights the seasonal variation in UV exposure, making December a more forgiving month for outdoor activities. For more detailed information, visit the Iwakuni UV Index.
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As winter descends upon Iwakuni, December brings a notable shift in sunshine hours, with the city basking in 220 hours of daylight. While this marks a decrease from the vibrant totals of the preceding spring and summer months, it still reflects a generous dose of sunlight compared to the earlier winter months. The trend shows a gradual decline from August's peak of 308 hours, suggesting that while the days may be getting shorter, Iwakuni's December still offers a significant sunny respite amid the crisp winter air. This charming blend of warmth and coolness makes December an enchanting time to explore the city's unique landscapes, where sunshine illuminates the beauty of the season.
In December, residents and visitors in Iwakuni, Japan, can look forward to a 55% chance of sunny weather, marking a noticeable increase compared to the preceding months. As the year nears its end, December's likelihood of sunshine stands out against the more subdued probabilities of July and June, which dip to 23% and 25% respectively. Notably, the fall months exhibit a gradual rise in sunny days, with November at 52%, setting the stage for this bright December. Although the winter season is just beginning, the prospects for sunshine are encouraging, suggesting that December might just offer a cheerful respite amidst the chilly weather.
In Iwakuni, Japan, the daylight duration experiences notable seasonal shifts throughout the year. Starting from December, the days are shorter, offering only 9 hours of daylight, which marks a transition into the darker winter months. As the year progresses into spring, daylight steadily increases, peaking in June and July with 14 hours of bright sunshine. The trend continues with May and April providing ample light at 13 hours, while the autumn months see a gradual decline back to 10 hours in November. This rhythmic ebb and flow of daylight not only enhances the beauty of Iwakuni’s changing seasons but also invites residents and visitors alike to embrace both the vibrant days of summer and the tranquil, reflective nights of winter.
As December unfolds in Iwakuni, Japan, the air begins to whisper with a gentle breeze, with average wind speeds reaching 3.3 m/s (7 mph). This slight uptick mirrors February's similar conditions, hinting at the briskness that winter often brings. Throughout the year, Iwakuni experiences a varied wind pattern, with the months of June and July often marked by calmer days, noted for their lower averages of 1.8 m/s (4 mph) and 2.0 m/s (5 mph). Surprisingly, the late fall into winter sees an increase in wind speeds, suggesting that while the chill sets in, it doesn't come without a spirited breath of air. Overall, December not only carries the promise of winter but also a refreshing gust that invigorates the landscape, inviting residents and visitors alike to embrace the season’s charm.
Weather in Iwakuni varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Iwakuni, focusing on differences in temperature, rainfall, humidity, and UV levels.
In December, the weather tends to be milder with average temperatures ranging from a minimum of -1°C (31°F) to a maximum of 20°C (69°F), while January sees cooler temperatures, with a minimum of -4°C (25°F) and a maximum of 15°C (59°F). Precipitation is slightly higher in December at 61 mm (2.4 in), compared to January's 49 mm (1.9 in), although both months experience rain for about six days. Humidity remains relatively consistent, with December at 75% and January slightly higher at 76%. For a more detailed look at January weather in Iwakuni, you can visit Iwakuni weather in January.
December and February present a subtle contrast in weather characteristics. In December, the temperatures range from a minimum of -1°C (31°F) to a maximum of 20°C (69°F), with an average of 7°C (46°F). The month sees about 61 mm (2.4 in) of precipitation over six days, accompanied by a relatively high humidity level of 75%. In comparison, February experiences slightly cooler temperatures, with a minimum of -4°C (26°F) and an average of 6°C (43°F), while the maximum remains similar at 20°C (68°F). Precipitation increases to 69 mm (2.7 in) over seven days, and humidity is a touch lower at 72%. For more detailed insights about February weather, you can explore Iwakuni weather in February.
In December, temperatures in Iwakuni typically range from a chilly minimum of -1°C (31°F) to a mild maximum of 20°C (69°F), with an average of 7°C (46°F). The month sees a moderate amount of precipitation, averaging 61 mm (2.4 in) over approximately 6 days, combined with a relatively high humidity level of 75%. In contrast, March experiences slightly warmer temperatures, with a minimum of 1°C (33°F) and a maximum reaching 22°C (71°F), resulting in an average of 10°C (50°F). However, March is also wetter, with precipitation levels rising to 125 mm (4.9 in) across about 10 days, while humidity decreases slightly to 69%. For more detailed information about March weather, visit Iwakuni weather in March.
December and April present distinct weather patterns. In December, temperatures range from a chilly minimum of -1°C (31°F) to a mild maximum of 20°C (69°F), with an average temperature of 7°C (46°F). The month sees about 61 mm (2.4 in) of precipitation over six days, maintaining a humidity level of 75%. In contrast, April boasts a more moderate climate with minimum temperatures of 2°C (36°F) and maximums reaching 24°C (76°F), averaging 14°C (58°F). However, it experiences significantly more rainfall, totaling 137 mm (5.4 in) across nine days, while humidity remains consistent at 75%. For more detailed information, you can explore Iwakuni weather in April.
In December, temperatures in Iwakuni can range from a chilly -1°C (31°F) at night to a mild 20°C (69°F) during the day, with an average of 7°C (46°F). The month sees about 61 mm (2.4 in) of precipitation, typically falling over six days, and the humidity levels hover around 75%. In contrast, May brings much warmer weather, with temperatures ranging from a minimum of 7°C (45°F) to a maximum of 28°C (83°F) and an average of 19°C (66°F). Rainfall increases to 136 mm (5.4 in) over nine days, and humidity rises slightly to 84%. For a more detailed look at the climate in May, check Iwakuni weather in May.
In December, weather conditions are notably cooler, with temperatures ranging from a minimum of -1°C (31°F) to a maximum of 20°C (69°F), and an average of 7°C (46°F). The month experiences moderate precipitation, totaling around 61 mm (2.4 in) over approximately 6 days, accompanied by a humidity level of 75%. In contrast, June offers a much warmer and more humid climate, with temperatures varying from a minimum of 14°C (57°F) to a maximum of 29°C (85°F) and an average of 22°C (72°F). The month sees significantly higher rainfall, about 181 mm (7.1 in) over 14 days, and a humidity level that rises to 88%. For more detailed information, you can check out Iwakuni weather in June.
December and July present stark contrasts in weather. In December, temperatures range from a chilly -1°C (31°F) at night to a mild average of 7°C (46°F) during the day, with a maximum reaching up to 20°C (69°F). This month experiences approximately 61 mm (2.4 in) of precipitation spread over 6 days, coupled with a humidity level of 75%. Conversely, July boasts significantly warmer temperatures, with nighttime lows of 18°C (65°F) and daytime averages soaring to 26°C (79°F), peaking at 35°C (95°F). Rainfall is much more pronounced in July, totaling 386 mm (15.2 in) over 19 days, accompanied by high humidity at 95%. The contrast between the dry, crisp air of December and the humid warmth of July highlights the diverse climate throughout the year. For more specific details on July weather, you can check Iwakuni weather in July.
In December, the weather in Iwakuni is much cooler, with temperatures ranging from a low of -1°C (31°F) to a comfortable high of 20°C (69°F), averaging around 7°C (46°F). The month sees some precipitation, totaling 61 mm (2.4 in) over about 6 days, with humidity levels hovering around 75%. In contrast, August experiences significantly warmer weather, with temperatures starting from a minimum of 20°C (67°F) and peaking at 35°C (96°F), averaging around 28°C (82°F). This summer month is considerably wetter, with 256 mm (10.1 in) of rainfall spread over approximately 14 days, and higher humidity at 93%. For more detailed information on the weather during this summer month, you can check Iwakuni weather in August.
December and September exhibit striking contrasts in weather. While September boasts warmer temperatures, with averages around 24°C (75°F) and maximums reaching up to 33°C (92°F), December presents a much cooler climate, featuring an average temperature of 7°C (46°F) and a maximum of just 20°C (69°F). In terms of precipitation, September is significantly wetter, receiving 237 mm (9.3 in) over 14 days compared to December's 61 mm (2.4 in) over just 6 days. Additionally, humidity levels are higher in September at 84%, contrasted with December's 75%. For more detailed information, you can check out Iwakuni weather in September.
In comparing the weather of December and October, December presents lower temperatures, with a minimum of -1°C (31°F) and an average of 7°C (46°F), while October enjoys milder conditions, featuring a minimum of 8°C (46°F) and an average of 19°C (66°F). Rainfall is significantly higher in October, with 172 mm (6.8 in) of precipitation over 10 days, compared to December's 61 mm (2.4 in) over just 6 days. Additionally, humidity is slightly elevated in October at 79%, compared to December’s 75%. For a more detailed look at October's weather, visit Iwakuni weather in October.
In comparing the weather between December and November, December experiences cooler temperatures, with a minimum of -1°C (31°F) compared to November's minimum of 2°C (36°F). The average temperature in December is also lower at 7°C (46°F) versus November's 13°C (55°F). Despite December being cooler, it does see slightly more rainfall with 61 mm (2.4 in) over 6 days, compared to November's 37 mm (1.5 in) over 5 days. Humidity levels are relatively similar, with December at 75% and November at 76%. For a more detailed look at November's weather, you can check Iwakuni weather in November.
As December arrives in Iwakuni, the weather takes on a distinctly cooler character, with temperatures dipping to a cozy average of 7°C (46°F). Unlike the warmer months, where balmy conditions prevail, December often brings brisk mornings and chilly evenings, making it a time for layering up. Precipitation, while present, is relatively modest, contributing to the month’s crisp air without the washout days typical of the rainy season. Humidity remains high, adding a touch of dampness to the chill, but overall, December’s climate fosters a unique charm that’s perfect for enjoying the last of autumn's beauty. For more details on the area's weather patterns, visit Iwakuni Climate.