Last updated: August 21, 2025
January in Unzen, Japan showcases a cool yet refreshing climate, with temperatures ranging from a maximum of 19°C (66°F) to a minimum of -2°C (29°F). The average temperature hovers around a crisp 8°C (46°F), providing a brisk atmosphere ideal for winter exploration. Visitors can anticipate 53 mm (2.1 in) of precipitation spread over 6 days, contributing to a humidity level of 75% that envelops the region in a refreshing, misty ambiance. This unique blend of cool temperatures and moderate rainfall creates a serene winter landscape, perfect for experiencing the natural beauty of Unzen.
In Unzen, Japan, January temperatures present a distinct chill, with minimums dipping to -2°C (29°F) and an average of 8°C (46°F). Daily highs can reach up to 19°C (66°F), creating a crisp but refreshing winter atmosphere. As the month progresses into February, temperatures hold steady, maintaining the same minimum but slightly warming the average to 8°C (48°F). This trend of gradual warming continues into March, where minimums rise to 3°C (37°F) and average temperatures reach 12°C (55°F), hinting at the approaching spring. The consistent increase in temperatures over the following months showcases an inviting transition from the winter cold, with April and May boasting averages of 16°C (62°F) and 21°C (69°F) respectively, further emphasizing Unzen's shift from its winter chill to a more temperate climate as spring unfolds.
In January, Unzen experiences a relatively modest precipitation total of 53 mm (2.1 in), falling on just six days. This marks the beginning of a gradual increase in rainfall that continues through the winter and peaks dramatically in the summer months. By February, precipitation rises to 92 mm (3.6 in), with more frequent rain days, setting the stage for the wetter months ahead. As spring blooms, the city sees a steady climb, reaching 145 mm (5.7 in) in March and 135 mm (5.3 in) in April. This trend escalates significantly as June and July approach, with July alone accumulating an impressive 475 mm (18.7 in) over 19 days—making it the wettest month. Overall, January serves as a prelude to the lush greenery that later springs to life as the region prepares for its more torrential summer rains.
In January, Unzen, Japan experiences a relatively high humidity level at 75%, setting the stage for the wetter months to come. As winter transitions into spring, February and March see a slight decline, maintaining a steady 71%. However, the humidity begins to rise again in April, peaking at 78% as the region gears up for the summer months. By May, the humidity spikes to 84%, reaching a peak of 92% in July, marking the height of the summer season. This trend continues into August with a slight decrease to 91%, before the humidity starts to taper off in the fall. September marks a decline to 84%, followed by a gradual decrease through October and December, stabilizing around 79% in January. This cyclical pattern highlights the distinct seasonal shifts in Unzen's weather, characterized by a humid summer and a more temperate winter.
In January, Unzen, Japan, experiences a moderate UV Index of 4, which allows for a burn time of approximately 30 minutes under direct sunlight. As winter transitions into spring, the UV levels begin to rise sharply; by February, the index increases to 6, categorized as high, with a reduced burn time of 25 minutes. This upward trend continues dramatically into March, reaching an intensity of 8 (very high) and a burn time of only 15 minutes. By the time April rolls around, the UV Index escalates to 11, classified as extreme, reflecting a clear warning for sun safety with a minimal burn time of just 10 minutes. Remarkably, this extreme level persists through the summer months until September, when the index dips slightly to 11 once again. As autumn approaches, the UV Index falls, moving back to high levels of 6 in November and returning to moderate at 4 by December. Overall, the data indicates a significant fluctuation in UV exposure, emphasizing the need for sun protection, especially during the spring and summer months. For more detailed insights on UV levels throughout the year, visit Unzen UV Index.
UV Risk Categories
In January, Unzen, Japan, welcomes 180 hours of sunshine, marking the start of the year with a gentle embrace of light. As winter gives way to spring, the sunshine steadily increases, peaking in August at a bright 300 hours. This upward trend across the months highlights a vibrant transition, with March and April showing significant boosts in sunlight to 264 and 282 hours, respectively. Even as summer arrives, the sunshine remains plentiful, with July and August providing a warm, sun-soaked atmosphere. As autumn sets in, the hours begin to taper off, yet October and November still enjoy commendable light with 258 and 237 hours. Overall, the year in Unzen beautifully captures a rhythm of increasing brightness, culminating in a glorious summer before gracefully winding down to winter.
In January, Unzen, Japan experiences a 38% chance of sunny weather, making it a relatively bright start to the year. This likelihood is slightly lower than February's 44%, suggesting that the sun tends to shine a bit more as winter progresses. Interestingly, the trend continues into spring with March seeing a 37% chance, and while April offers a modest increase to 41%, the chances dip again in May to just 28%. This pattern highlights how weather in Unzen can fluctuate significantly, particularly during the transitional months leading to summer, where sunshine becomes less frequent with only 20% likelihood in July. As the year progresses toward autumn, the chances of sunny days rebound sharply, peaking at 64% in October, showcasing the region's vibrant and varied climate throughout the seasons.
In Unzen, Japan, January marks the beginning of a gradual increase in daylight, offering around 10 hours as winter starts to retreat. This trend continues into February and March, with daylight extending to 11 hours. By the time April rolls around, the days grow notably longer, reaching 12 hours, and May ushers in a vibrant 13 hours of sunlight, illuminating the stunning landscapes. June and July peak at 14 hours, creating a perfect backdrop for outdoor adventures. As summer fades into autumn, daylight begins to wane, gently descending to 13 hours in August and 12 hours in September. October sees a further reduction to 11 hours, while November and December settle back at 10 hours, marking the return of winter's early twilight. This cyclical pattern of increasing and decreasing daylight not only enhances the natural beauty of Unzen but also invites visitors to experience its diverse seasonal charms.
In January, the winds in Unzen, Japan, offer a refreshing start to the year with an average speed of 3.0 m/s (7 mph), making it one of the breezier months. Following this, February sees a slight increase to 3.1 m/s (7 mph), while March marks a small decline to 2.8 m/s (6 mph), hinting at the gradual transition towards spring. As the months progress, April and May experience a steady drop, showcasing average speeds of 2.7 m/s (6 mph) and 2.6 m/s (6 mph), respectively. A noticeable shift occurs in June with winds calming to 1.6 m/s (4 mph), establishing a trend of milder breezes during the summer months. While the wind picks up marginally in July and August at around 2.5 to 2.7 m/s (6 mph), it tapers off again by September and into the autumn. December brings a slight resurgence to 2.8 m/s (6 mph), wrapping up the year with a gentle reminder of winter's breath, illustrating a compelling ebb and flow in Unzen's wind patterns throughout the seasons.
Weather in Unzen varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Unzen, focusing on differences in temperature, rainfall, humidity, and UV levels.
In January, the weather features a chilly minimum temperature of -2°C (29°F) and an average of 8°C (46°F), while the maximum can reach up to 19°C (66°F). The month sees a total precipitation of 53 mm (2.1 in) over approximately 6 days, with humidity levels around 75%. In contrast, February maintains the same minimum temperature of -2°C (29°F) but experiences a slight increase in average temperature to 8°C (48°F), and a higher maximum of 22°C (71°F). Additionally, precipitation rises to 92 mm (3.6 in) over 9 days, with humidity dipping slightly to 71%. For more detailed insights, you can check Unzen weather in February.
January and March exhibit notable contrasts in weather conditions. January typically experiences cooler temperatures, with averages ranging from a minimum of -2°C (29°F) to a maximum of 19°C (66°F), while March sees a rise in temperatures, ranging from a minimum of 3°C (37°F) to a maximum of 24°C (76°F). Precipitation levels also differ, with January receiving 53 mm (2.1 in) over 6 days, compared to March's more substantial 145 mm (5.7 in) across 11 days. Additionally, humidity in January hovers around 75%, slightly higher than March's 71%. For a more detailed look at March weather conditions, you can visit Unzen weather in March.
January weather tends to be quite chilly, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 19°C (66°F) and an average of 8°C (46°F). The month experiences relatively low precipitation, with about 53 mm (2.1 in) over 6 days, while the humidity hovers around 75%. In contrast, April brings significantly warmer conditions, with temperatures soaring from a minimum of 5°C (41°F) to a maximum of 29°C (84°F), averaging 16°C (62°F). However, April is also wetter, receiving 135 mm (5.3 in) of rain across 8 days and slightly higher humidity at 78%. For more details on the typical weather in April, check out Unzen weather in April.
In comparing January and May weather, the contrast is striking. January experiences cooler temperatures, ranging from a minimum of -2°C (29°F) to a maximum of 19°C (66°F), with an average of 8°C (46°F). The month sees relatively low precipitation of 53 mm (2.1 in) over about 6 days, accompanied by a humidity level of 75%. In stark contrast, May boasts warmer temperatures, with a minimum of 10°C (50°F) and a maximum reaching 30°C (86°F), averaging 21°C (69°F). However, it also brings significantly more rainfall, totaling 214 mm (8.4 in) across 12 days, and a higher humidity level of 84%. For a closer look at May weather in Unzen, you can visit Unzen weather in May.
In January, the weather is quite cool, with temperatures ranging from a chilly -2°C (29°F) at night to a mild 19°C (66°F) during the day. The month typically sees about 53 mm (2.1 in) of precipitation over approximately 6 days, accompanied by a humidity level of 75%. In stark contrast, June brings a significant warm-up, with temperatures soaring from a minimum of 16°C (60°F) to a maximum of 32°C (90°F), averaging around 24°C (75°F). This month is much wetter, with 262 mm (10.3 in) of rainfall spread over 15 days and humidity rising to 86%. For further details on the weather conditions specific to June, you can visit Unzen weather in June.
In January, the weather is relatively cool, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 19°C (66°F), averaging around 8°C (46°F). The month sees moderate precipitation of 53 mm (2.1 in) over about 6 days, accompanied by a humidity level of 75%. In stark contrast, July experiences much warmer temperatures, with a minimum of 20°C (68°F) and a maximum soaring up to 37°C (99°F), averaging 27°C (82°F). This summer month also brings significant rainfall, with precipitation reaching 475 mm (18.7 in) over 19 days, while humidity levels rise to a humid 92%. For more details on the weather in July, check out Unzen weather in July.
In January, the weather is quite cool, with temperatures ranging from a minimum of -2°C (29°F) to a comfortable maximum of 19°C (66°F) and an average of about 8°C (46°F). The month experiences relatively low precipitation at 53 mm (2.1 in) over approximately 6 days, with humidity levels around 75%. In contrast, August brings significantly warmer temperatures, with a minimum of 20°C (68°F), an average high of 29°C (85°F), and peaks soaring up to 39°C (102°F). This month is much wetter, receiving 303 mm (11.9 in) of rain over about 14 days and higher humidity at 91%. For more details on August weather, visit Unzen weather in August.
January and September present starkly different weather conditions. In January, temperatures can range from a chilly -2°C (29°F) at night to a mild 19°C (66°F) during the day, with an average of 8°C (46°F). This month typically sees about 53 mm (2.1 in) of precipitation over approximately 6 days, along with a humidity level of 75%. In contrast, September warms up significantly, with nighttime lows around 16°C (62°F) and daytime highs reaching up to 35°C (94°F), averaging 25°C (78°F). This month experiences much heavier rainfall, totaling 228 mm (9.0 in) over 15 days, and humidity increases to 84%. For those interested in the specifics of September weather in Unzen, you can find more information here.
January and October present markedly different weather conditions. In January, temperatures range from a chilly -2°C (29°F) at night to a mild 19°C (66°F) during the day, with an average of 8°C (46°F). Precipitation in January totals 53 mm (2.1 in) over about 6 days, and humidity sits at a comfortable 75%. In contrast, October experiences significantly warmer weather, with nighttime lows of 10°C (50°F) and daytime highs reaching up to 33°C (91°F), averaging around 21°C (69°F). This month also receives more rainfall, totaling 120 mm (4.7 in) across approximately 9 days, coupled with a slightly higher humidity of 83%. For more details on the weather in October, you can visit Unzen weather in October.
In comparing the weather between January and November, there are notable differences in temperature and precipitation patterns. January experiences cooler temperatures, with a minimum of -2°C (29°F) and an average of 8°C (46°F), while November boasts a milder minimum of 3°C (38°F) and an average of 15°C (59°F). The maximum temperatures are also higher in November, reaching up to 25°C (78°F) compared to January’s maximum of 19°C (66°F). Additionally, November sees more precipitation, totaling 80 mm (3.1 in) over 8 days, in contrast to January's 53 mm (2.1 in) over 6 days. Humidity levels are slightly higher in November at 81%, compared to 75% in January. For more detailed information about November weather, you can visit Unzen weather in November.
In January, the weather is generally cooler than in December, with average temperatures ranging from a minimum of -2°C (29°F) to a maximum of 19°C (66°F). In contrast, December enjoys milder temperatures, with a minimum of 0°C (33°F) and a maximum reaching up to 24°C (76°F). Additionally, January experiences less precipitation at 53 mm (2.1 in) over 6 days, compared to December's 89 mm (3.5 in) across 7 days. Humidity levels are slightly lower in January at 75%, while December has a higher humidity at 79%. For more details on December's weather, you can check Unzen weather in December.
In January, Unzen experiences a distinctive chill, characterized by cooler temperatures and notable humidity levels. With average temperatures hovering around 8°C (46°F), the month stands in contrast to the milder seasons that envelop the region in spring and summer. While there are fewer sunny days, the 53 mm of precipitation that falls over six days adds a refreshing element to the landscape. This combination of cooler weather and moisture creates a unique atmosphere, perfect for those looking to experience Unzen's natural beauty in a quieter, more serene setting. For a deeper look into what to expect throughout the year, explore Unzen Climate.