Last updated: August 21, 2025
January in Iwakuni, Japan experiences a mix of chilly and mild weather. During this month, temperatures range from a maximum of 15°C (59°F) to a brisk minimum of -4°C (25°F), with an average hovering around 5°C (42°F). The atmosphere is quite humid, with relative humidity sitting at 76%, which can make the cold feel more biting. Rain is not uncommon, as the region sees 49 mm (1.9 in) of precipitation over approximately six days. This combination of cool temperatures and moisture creates a unique winter ambiance in Iwakuni, making it a captivating time to explore the city and its surroundings.
In Iwakuni, Japan, January brings a chill, with temperatures ranging from a brisk -4°C (25°F) at night to a pleasant 15°C (59°F) during the day. This month acts as a transitional period, marking the coldest point of winter before temperatures gradually begin to rise in February. Here, the average temperature inches up to 6°C (43°F), hinting at the mild turns ahead. As we move from January into spring, the warming trend becomes more pronounced, with March's average climbing to 10°C (50°F) and reaching 22°C (71°F) by the end of the month. The shift from winter's frosty grasp to the gentle embrace of spring is truly captivating, showcasing Iwakuni's evolving climate as it transitions to more temperate conditions.
In January, Iwakuni, Japan experiences relatively mild precipitation, with an average of 49 mm (1.9 in) spread across just 6 days of the month. This marks the beginning of the year with a gentle start, contrasting sharply with the heavier rainfall that follows in the coming months. As winter transitions to spring, February sees a noticeable increase to 69 mm (2.7 in) over 7 days, and by March, precipitation jumps to 125 mm (4.9 in) within 10 days. The trend continues upward, peaking dramatically in July with an astonishing 386 mm (15.2 in) over 19 days, highlighting the wet season's intensity. This pattern illustrates a distinct seasonal rhythm in Iwakuni's climate, where January's light showers transition into a robust monsoon season, emphasizing the diverse weather conditions that characterize the region.
In Iwakuni, Japan, January sets the stage with a relatively high humidity level of 76%, establishing a pattern that persists through the winter months. As February and March arrive, humidity gradually diminishes to 72% and 69%, respectively, hinting at a transition toward warmer days. However, this shift is short-lived, as April sees a slight uptick to 75%, paving the way for May's significant surge to 84%. This upward trajectory continues into the summer, reaching a peak in July at a staggering 95%. The trend remains high throughout August with 93% before tapering off into the fall months, bringing September down to 84% and settling at 79% in October. By November and December, humidity gently stabilizes around 76% and 75%, closing the year with a familiar, moist embrace that characterizes Iwakuni's climate.
In January, Iwakuni, Japan, experiences a modest UV Index of 4, placing it in the moderate exposure category, where a burn can occur in about 30 minutes. As the year progresses into February, the UV Index rises slightly to 5, maintaining the same moderate classification. A more significant shift occurs by March, with the index climbing to 8, signaling a transition to very high exposure and reducing the safe sun exposure time to just 15 minutes. This trend continues to escalate, peaking in April, May, June, and July with an extreme UV Index of 11 to 12, highlighting the importance of sun protection during these months, where even minimal exposure can lead to burns in just 10 minutes. By August, the UV levels remain high before gradually tapering off in the fall, with October and November showcasing more manageable indices of 7 and 6 respectively. As the year comes to a close in December, the UV Index drops back to a moderate level of 4, echoing its January status. Planning your sun exposure with awareness of these trends is crucial for skin protection. For more detailed information, visit the Iwakuni UV Index.
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In Iwakuni, Japan, January heralds the year with 184 hours of sunshine, marking the beginning of a gradual increase in daylight as winter yields to spring. As February arrives, the sunny hours rise to 227, and by March, residents bask in 266 hours of sunshine, signaling a clear shift toward brighter days. April continues this trend, offering 282 hours, while May shines even brighter with 303 hours, peaking as the days grow longer. The summer months, particularly August, boast the most hours of sunshine at 308, yet as autumn approaches, the hours begin to wane, with September at 260 hours and October slightly less at 254. November and December continue this decline, but even in the depths of winter, the 220 hours in December remind us of the enduring beauty of Iwakuni's climate, where each season unfolds its unique charm through a spectrum of sunlight.
In Iwakuni, Japan, the likelihood of sunny weather in January stands at 43%, making it one of the more promising winter months. Interestingly, this percentage shows a slight dip compared to February’s 50%, which is the month with the highest chance of sunshine leading into spring. Following January, the likelihood fluctuates with March seeing a decline to 40%, hinting at a transitional shift as winter gradually gives way to spring. However, as the calendar moves toward the brighter months, April picks up slightly at 47%. In contrast, the summer months drop significantly, highlighting June and July's notably lower chances of sunny days at 25% and 23%, respectively. Overall, while January's sunshine chances aren't the highest, they set a positive tone for the year ahead, standing out amidst a winter backdrop before the weather begins to warm and clear later in the year.
In Iwakuni, Japan, January marks the beginning of the year with just 10 hours of daylight, a trend that holds steady into February. As spring approaches, daylight begins to lengthen, reaching 11 hours by March. The shift becomes more pronounced in April and May, where the daylight stretches to 13 hours, inviting the vibrant blooms of early summer. June and July offer the longest days, with 14 hours of sunlight, perfect for outdoor activities and enjoying the warm weather. As summer fades, daylight gradually decreases, starting from 13 hours in August to 12 hours in September. The descent continues into the fall and winter months, dropping back to 10 hours in November and reaching its lowest point in December with just 9 hours of daylight. This seasonal rhythm showcases Iwakuni's dynamic transition from winter's short days to summer's extended sunlight, providing a captivating backdrop to the passing year.
In January, Iwakuni, Japan, greets the new year with a brisk average wind speed of 3.1 m/s (7 mph), setting a lively tone for the winter months. As the season progresses into February, the winds pick up slightly to 3.3 m/s, contributing to a refreshed ambiance. However, by March and continuing through April and May, wind speeds settle down to a consistent 2.8 m/s (6 mph), giving a calmer feel as spring approaches. The summer months bring a gentle decline, with June seeing a noticeable drop to 1.8 m/s (4 mph), where the air feels more tranquil. This trend of softer breezes continues into July and August, maintaining an average of about 2.0-2.6 m/s. As the year winds down, September and October see a stable return to the earlier rates of 2.3 m/s, before a slight uptick in November and December brings us back to the winter invigorations, both registering 2.8 m/s and 3.3 m/s, respectively. This rhythm of wind speeds illustrates the dynamic seasonal transitions in Iwakuni, with January marking a bold start to a year of change.
Weather in Iwakuni varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Iwakuni, focusing on differences in temperature, rainfall, humidity, and UV levels.
In January, temperatures in Iwakuni tend to range from a minimum of -4°C (25°F) to a maximum of 15°C (59°F), with an average temperature of 5°C (42°F). The month sees around 49 mm (1.9 in) of precipitation over approximately six days, contributing to a relatively high humidity level of 76%.
Conversely, February brings slightly warmer conditions, with temperatures ranging from -4°C (26°F) to a maximum of 20°C (68°F), and an average temperature of 6°C (43°F). Precipitation increases to 69 mm (2.7 in) over seven days, while humidity decreases slightly to 72%. For more details on February's weather, you can check Iwakuni weather in February.
January weather is characterized by colder temperatures, with a minimum of -4°C (25°F) and an average of 5°C (42°F). It experiences lower humidity at 76% and less precipitation, totaling 49 mm (1.9 in) over just 6 days. In contrast, March sees a significant warming trend, with temperatures ranging from a minimum of 1°C (33°F) to a maximum of 22°C (71°F) and an average of 10°C (50°F). The month also brings more rainfall, with 125 mm (4.9 in) over 10 days, alongside a slightly lower humidity level of 69%. For more specifics about the weather conditions during this time, you can visit Iwakuni weather in March.
In January, the weather tends to be quite cold, with temperatures ranging from a frigid minimum of -4°C (25°F) to a maximum of 15°C (59°F) and an average of around 5°C (42°F). Precipitation is relatively light, totaling 49 mm (1.9 in) over approximately six days, while humidity hovers around 76%. In contrast, April ushers in a significant warming trend, featuring milder temperatures with a minimum of 2°C (36°F) and an average of 14°C (58°F), peaking at a comfortable 24°C (76°F). However, April also sees increased rainfall, accumulating 137 mm (5.4 in) across nine days, while humidity remains similar at 75%. For more details about the climate during this month, check out Iwakuni weather in April.
January and May exhibit stark contrasts in weather conditions. In January, temperatures range from a chilly -4°C (25°F) to a mild 15°C (59°F), with an average of 5°C (42°F). The month sees 49 mm (1.9 in) of precipitation over about 6 days, accompanied by a relatively high humidity of 76%. Conversely, May brings a significant warm-up, 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). Precipitation also increases to 136 mm (5.4 in) over 9 days, with humidity rising slightly to 84%. For a detailed look at the climatic nuances, check out Iwakuni weather in May.
The weather in January is notably cooler, with temperatures ranging from a chilly minimum of -4°C (25°F) to a mild maximum of 15°C (59°F) and an average temperature of 5°C (42°F). In contrast, June brings much warmer conditions, with temperatures fluctuating between a minimum of 14°C (57°F) and a maximum of 29°C (85°F), resulting in a comfortable average of 22°C (72°F). Additionally, January experiences only 49 mm (1.9 in) of precipitation over 6 days, while June sees a significant increase to 181 mm (7.1 in) spread across 14 days, paired with higher humidity levels of 88%. For more details on June weather, you can check Iwakuni weather in June.
January and July present stark contrasts in weather conditions. In January, temperatures average around 5°C (42°F), with minimums dipping as low as -4°C (25°F) and maximums reaching up to 15°C (59°F). The month experiences 49 mm (1.9 in) of precipitation over approximately 6 days, accompanied by a relatively high humidity of 76%. In contrast, July boasts much warmer temperatures, averaging 26°C (79°F) with minimums of 18°C (65°F) and maximums soaring to 35°C (95°F). This summer month is considerably wetter, with 386 mm (15.2 in) of rain spread across 19 days, leading to a much higher humidity level of 95%. For more detailed information, check out Iwakuni weather in July.
January and August present two contrasting weather patterns. In January, temperatures range from a chilly -4°C (25°F) at night to a mild 15°C (59°F) during the day, with an average of 5°C (42°F). Precipitation is relatively low, with only 49 mm (1.9 in) over approximately six days and a humidity level of 76%. In stark contrast, August boasts considerably warmer temperatures, with a minimum of 20°C (67°F) and a maximum reaching 35°C (96°F), averaging 28°C (82°F). However, this summer month sees significantly more rainfall, totaling 256 mm (10.1 in) over 14 days, coupled with higher humidity at 93%. For a detailed look at Iwakuni's climate, check out Iwakuni weather in August.
In January, the weather is characterized by much colder temperatures, with a minimum of -4°C (25°F) and an average of 5°C (42°F), reaching a maximum of 15°C (59°F). Precipitation is relatively low at 49 mm (1.9 in) over only 6 days, and the humidity is moderate at 76%. In stark contrast, September experiences significantly warmer conditions with temperatures ranging from a minimum of 15°C (60°F) to a maximum of 33°C (92°F), averaging around 24°C (75°F). This month sees much higher precipitation levels, totaling 237 mm (9.3 in) over 14 days, and the humidity rises to 84%. For more detailed information on September weather, visit Iwakuni weather in September.
In January, Iwakuni experiences cooler temperatures, with a minimum of -4°C (25°F) and an average of 5°C (42°F), reaching a maximum of 15°C (59°F). Precipitation is moderate, totaling 49 mm (1.9 in) over about six days, and the humidity hovers around 76%.
In contrast, October brings much milder weather, with temperatures ranging from a minimum of 8°C (46°F) to a pleasant maximum of 29°C (85°F), averaging 19°C (66°F). This month sees significantly higher precipitation, totaling 172 mm (6.8 in) over approximately ten days, and a slight increase in humidity to 79%. For more details, you can check Iwakuni weather in October.
In January, the weather is significantly colder compared to November, with average temperatures ranging from a chilly -4°C (25°F) to a maximum of 15°C (59°F). In contrast, November experiences milder temperatures, with a range from 2°C (36°F) to a warm 23°C (74°F). Both months see similar levels of humidity, around 76%, but January has slightly more precipitation at 49 mm (1.9 in) over 6 days, while November has 37 mm (1.5 in) spread over just 5 days. For more detailed information on November's climate, you can check Iwakuni weather in November.
In January, the weather is generally colder, with temperatures ranging from a minimum of -4°C (25°F) to a maximum of 15°C (59°F), resulting in an average temperature of 5°C (42°F). In comparison, December is milder, with minimum temperatures of -1°C (31°F) and maximums reaching 20°C (69°F), leading to a higher average of 7°C (46°F). Additionally, January sees slightly less precipitation at 49 mm (1.9 in) over 6 days, while December experiences more rainfall, totaling 61 mm (2.4 in) over the same number of days. Humidity levels are comparable, with January at 76% and December slightly lower at 75%. For a detailed overview of the month, check out Iwakuni weather in December.
In January, Iwakuni experiences a distinctly cooler climate compared to other months, with temperatures dropping to their lowest point of the year. While daytime highs can reach a mild 15°C, the chilly nights can plunge to -4°C, offering a stark contrast that reminds residents and visitors alike of winter's presence. With 49 mm of precipitation spread over six days, January can feel quite wet, contributing to a notable humidity level of 76%. This month’s weather showcases the seasonal shift that envelops Iwakuni with crisp air, making it a unique time for those looking to embrace the heart of winter. For more insights on the local climate, visit Iwakuni Climate.