Last updated: August 21, 2025
In January, Koshima, Japan experiences a mild winter climate characterized by a maximum temperature of 21°C (70°F) and an average of 14°C (57°F). The city often sees minimum temperatures dip to around 6°C (44°F), creating a crisp atmosphere. Throughout the month, Koshima encounters 108 mm (4.2 in) of precipitation over approximately 12 days, contributing to its lush landscapes. Humidity levels hover around 72%, lending a unique charm to the region as it transitions into spring. Visitors can expect varied weather conditions, making it a fascinating time to explore the natural beauty of Koshima.
In Koshima, Japan, January marks the transition into winter, with temperatures ranging from a cool 6°C (44°F) at night to a pleasant 21°C (70°F) during the day, creating an average of 14°C (57°F). This month's temperature pattern reveals a mild winter climate that is notably warmer than many other regions, allowing for comfortable outings. As the month progresses into February, the warmth remains steady, with nighttime lows only slightly higher at 7°C (44°F) and daytimes reaching the same max of 21°C (70°F). This consistency hints at a gradually warming trend leading into spring, as the temperatures gently rise through March and April. Such a backdrop of moderate winter temperatures not only makes Koshima an inviting destination but also sets the stage for the blooming vibrancy of the following months.
In Koshima, Japan, January marks the beginning of the year with a modest precipitation total of 108 mm (or 4.2 inches), spread over 12 days. This sets a relatively calm tone compared to the months that follow; February sees a noticeable jump to 157 mm with 16 days of rainfall, hinting at the approach of the wetter spring season. As spring unfolds, March experiences a substantial increase to 213 mm and maintains a steady rhythm of 16 rainy days. The trend continues into April, where precipitation remains elevated at 186 mm across 12 days. This gradual escalation leads to the rainy season in June, where Koshima fully embraces its downpours, with 491 mm (a staggering 19.3 inches) falling over 19 days. Through this progression, January stands out as a relatively dry prelude, setting the stage for the lush, vibrant months that follow.
In Koshima, Japan, January ushers in a humidity level of 72%, laying the foundation for the gradually rising trend seen as the year unfolds. Following January, February experiences a slight dip to 68% before humidity climbs back to 72% in March. As spring extends into summer, the humidity takes a noticeable leap, reaching 79% in April and escalating to a peak of 90% by July. This midsummer high marks the pinnacle of humidity, after which levels begin to recede slightly, settling at 85% in August and then gradually decreasing through the fall months, culminating in 74% by December. This pattern reveals a clear seasonal shift, where Koshima experiences its most substantial moisture during the summer months, creating a lush and vibrant atmosphere.
In Koshima, Japan, January sets the stage for a gradual increase in ultraviolet (UV) exposure as the year unfolds. With a UV Index of 5, the risk is categorized as moderate, allowing for a burn time of about 30 minutes for fair-skinned individuals. This relatively mild beginning foreshadows a significant uptick in UV intensity, culminating in the extreme levels recorded from April to August, where the UV Index reaches as high as 13. As spring transitions to summer, protectiveness becomes essential, with burn times shrinking dramatically to just 10 minutes during those peak months. The trend continues into early autumn, before dipping back to 7 in November and returning to a moderate 5 by December. This annual cycle emphasizes the importance of sun safety, particularly as Koshima experiences some of its strongest UV rays during the warmer months. For more details and tips on sun safety, check out the Koshima UV Index.
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January in Koshima, Japan, ushers in 164 hours of sunshine, laying the foundation for a gradual ascent into sunnier months. As the year progresses, February witnesses a notable increase with 216 hours, heralding the arrival of spring. By March, the days grow longer and warmer, boasting 253 hours of sunshine, while April continues this upward trajectory with 273 hours. The peak of warmth arrives in the summer months, with July basking in an impressive 302 hours, followed by the hottest month, August, shining brightly with 319 hours. September sees a slight decline to 284 hours, but the sun continues to grace Koshima into October with 266 hours. As the year winds down, November and December bring a softer glow, with 238 and 204 hours of sunshine respectively. This striking pattern showcases a vibrant dance of increasing light through spring and summer, gradually tapering into autumn and winter, capturing the essence of Koshima’s seasonal beauty.
In January, Koshima, Japan experiences a 29% chance of sunny weather, marking it as one of the cooler months for sunshine. This modest likelihood is part of a broader trend, as the chances of sunny days typically rise through the early months of the year, peaking significantly in September at 46%. Interestingly, February shows a notable increase to 38%, hinting at a shift towards brighter conditions as winter wanes. As spring approaches, the chances fluctuate but remain relatively stable before dipping again in the summer months, suggesting that while January may be less favorable for sunshine, the subsequent months herald a gradual return of clearer skies.
In Koshima, Japan, January ushers in about 10 hours of daylight, marking the year's start with crisp, illuminating mornings. As winter gives way to spring, daylight gradually increases: February sees an hour more, while March maintains the trend with the same 11 hours. By April, the days lengthen to 12 hours, leading to the brilliant light of May with its 13 hours. This brightness culminates in June with the longest days of 14 hours, a perfect time for outdoor adventures. However, as summer transitions into fall, daylight begins to recede; July and August both hold steady at 13 hours, but by September, it dips to 12 hours. The descent continues through October and November, where daylight returns to 10 hours, only to hold steady again in December. Overall, Koshima’s daylight patterns beautifully reflect the rhythm of the seasons, showcasing an inviting stretch of light in the spring and a gentle retreat toward winter.
In Koshima, January ushers in a brisk average wind speed of 8.1 m/s (18 mph), setting a dynamic tone for the winter months. This invigorating breeze contrasts with the slightly stronger winds of February, which peaks at 9.6 m/s (21 mph), before dialing back to 8.0 m/s (18 mph) in March. As spring approaches, the winds become more playful, with an increase to 8.8 m/s (20 mph) in April, before softening again in the early summer months. Interestingly, May and June see a dip to 6.6 m/s (15 mph) and 6.3 m/s (14 mph), respectively, hinting at a seasonal lull. However, the winds regain strength in October and November, with averages climbing back to 7.4 m/s (17 mph) and 8.4 m/s (19 mph). This ebb and flow reflect the region's shifting climate, where each month brings a unique character to the air, shaping both the landscape and the spirit of Koshima.
Weather in Koshima varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Koshima, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather of January and February, both months experience similar average temperatures, with January ranging from a minimum of 6°C to a maximum of 21°C, and February slightly higher with a minimum of 7°C while maintaining the same maximum. However, February sees a notable increase in precipitation, totaling 157 mm over 16 days compared to January's 108 mm over 12 days. Additionally, the humidity in February is slightly lower at 68%, compared to January's 72%. For more specific details, you can check Koshima weather in February.
In comparing the weather of January and March, it's evident that March experiences a slightly warmer climate, with average temperatures rising from 14°C (57°F) in January to 16°C (62°F) in March. January has a maximum temperature of 21°C (70°F), while March matches this high, reaching 22°C (72°F). Precipitation also increases significantly in March, totaling 213 mm (8.4 in) over 16 days, compared to January's 108 mm (4.2 in) on 12 days. Interestingly, both months maintain the same humidity level at 72%, resulting in a consistently humid environment. For a closer look at March weather specifics, you can visit Koshima weather in March.
In January, Koshima experiences mild temperatures with a minimum of 6°C (44°F) and an average of 14°C (57°F), reaching a comfortable maximum of 21°C (70°F). The month sees fairly significant rainfall, totaling 108 mm (4.2 in) over 12 days, accompanied by a humidity level of 72%. In contrast, April brings warmer conditions, with minimum temperatures rising to 12°C (53°F) and an average of 19°C (66°F) peaking at 24°C (75°F). However, this month also experiences increased precipitation, totaling 186 mm (7.3 in) across the same number of rainy days, while humidity slightly rises to 79%. For more detailed insights, you can check Koshima weather in April.
In January, the weather in Koshima is relatively mild, with temperatures ranging from a minimum of 6°C (44°F) to a maximum of 21°C (70°F). The month sees about 108 mm (4.2 in) of precipitation spread over 12 days, accompanied by a humidity level of 72%. In contrast, May experiences warmer temperatures, with a minimum of 16°C (61°F) and reaching as high as 26°C (78°F), averaging 22°C (71°F). However, May is considerably wetter, receiving 273 mm (10.7 in) of rainfall over 13 days and a higher humidity of 83%. For more detailed information, you can check Koshima weather in May.
In comparing the weather between January and June, it's evident that January is much cooler, with temperatures ranging from a minimum of 6°C (44°F) to a maximum of 21°C (70°F), accompanied by an average temperature of 14°C (57°F). The month experiences moderate precipitation at 108 mm (4.2 in) over 12 days, with a humidity level of 72%. In contrast, June is significantly warmer, with temperatures starting at a minimum of 19°C (67°F) and peaking at 27°C (81°F), averaging 24°C (76°F). However, June also brings considerable rainfall, totaling 491 mm (19.3 in) over 19 days and a higher humidity of 86%. For more details on the weather in June, visit Koshima weather in June.
In January, Koshima experiences mild temperatures ranging from a minimum of 6°C (44°F) to a maximum of 21°C (70°F), with an average of 14°C (57°F). The month sees around 108 mm (4.2 in) of precipitation spread over approximately 12 days, accompanied by a humidity level of 72%. In contrast, July brings a substantial increase in warmth, with temperatures ranging from 23°C (73°F) to a peak of 30°C (86°F), averaging 27°C (81°F). The humidity rises to 90%, and rainfall also increases significantly to 281 mm (11.0 in) over about 17 days. For more detailed information, you can visit Koshima weather in July.
January and August exhibit stark contrasts in weather conditions. In January, temperatures range from a mild 6°C (44°F) at night to a pleasant 21°C (70°F) during the day, while the average hovers around 14°C (57°F). However, this month also sees significant rainfall, with 108 mm (4.2 in) spread over 12 days, contributing to a humidity level of 72%. In sharp contrast, August experiences much warmer temperatures, with minimums at 24°C (76°F) and maximums reaching up to 30°C (86°F), resulting in an average temperature of 28°C (82°F). This month is also wetter, with precipitation totaling 214 mm (8.4 in) across 16 days and a higher humidity of 85%. For more details, check out Koshima weather in August.
January and September exhibit striking differences in weather patterns. In January, temperatures range from a mild 6°C (44°F) at night to a pleasant 21°C (70°F) during the day, with an average of 14°C (57°F). The month experiences 108 mm (4.2 in) of precipitation over 12 days, accompanied by a humidity level of 72%. In contrast, September brings significantly warmer temperatures, with night lows around 22°C (72°F) and daytime highs soaring to 29°C (84°F), averaging 27°C (80°F). Moreover, this month sees a much higher precipitation of 256 mm (10.1 in) spread over 20 days, coupled with increased humidity at 80%. For more details on weather conditions during this time, check Koshima weather in September.
In January, the weather in Koshima is cooler, with temperatures ranging from a minimum of 6°C (44°F) to a maximum of 21°C (70°F) and an average of 14°C (57°F). The month sees around 108 mm (4.2 in) of precipitation over 12 days, accompanied by a relative humidity of 72%. In contrast, October brings milder weather, with temperatures ranging from a minimum of 18°C (65°F) to a maximum of 27°C (81°F) and an average of 24°C (75°F). October is also wetter, with 164 mm (6.4 in) of rainfall over 13 days and slightly higher humidity at 78%. For more detailed insights, you can check Koshima weather in October.
In January, temperatures range from a minimum of 6°C (44°F) to a maximum of 21°C (70°F), with an average of 14°C (57°F). The month sees approximately 108 mm (4.2 in) of precipitation over 12 days, accompanied by a humidity level of 72%. In contrast, November offers milder weather, with temperatures starting at a minimum of 13°C (56°F) and peaking at 25°C (78°F), averaging around 20°C (68°F). The precipitation is slightly higher at 150 mm (5.9 in) spread across 13 days, and humidity is a bit elevated at 76%. For further details, check out Koshima weather in November.
In January, the weather is slightly cooler than in December, with average temperatures ranging from a minimum of 6°C (44°F) to a maximum of 21°C (70°F) compared to December's range of 8°C (46°F) to 24°C (75°F). January experiences a bit less rainfall than December, recording 108 mm (4.2 in) over 12 days, whereas December sees 132 mm (5.2 in) over 14 days. Despite the minor differences, both months exhibit high humidity, with January at 72% and December slightly higher at 74%. For a detailed look at December's climate, visit Koshima weather in December.
As January unfolds in Koshima, the weather presents a cooler and wetter backdrop compared to the milder months ahead. With an average temperature hovering around 14°C, there's a refreshing chill in the air, while occasional peaks at 21°C remind us of the warmth yet to come. This month experiences notable rainfall, with precipitation occurring on about 12 days, contributing to the region's lush landscape. The 72% humidity enhances the coolness of the air, creating a unique atmosphere reflective of winter's grip. For those planning a visit or simply curious about Koshima’s distinct climate, you can explore more details at Koshima Climate.