Last updated: October 30, 2025
In January, Jeju City, South Korea experiences a diverse range of weather conditions. With maximum temperatures reaching 19°C (66°F) and a chilling minimum of -2°C (29°F), the average hovers around a cool 6°C (44°F). The month is characterized by 10 days of precipitation, accumulating 58 mm (2.3 in) on average, contributing to a humidity level of 72%. This blend of cool temperatures and frequent rain creates a unique atmosphere, making January a particularly intriguing time to explore the natural beauty of Jeju Island.
In January, Jeju City's temperatures start off distinctly cool, with minimums dipping to -2°C (29°F), heralding the winter chill. The average temperature reaches a modest 6°C (44°F), while daytime highs can climb to a comfortable 19°C (66°F). This month marks the transition from frosty mornings to milder afternoons, hinting at the gradual warming trend approaching in February and onward. As winter loosens its grip, visitors can enjoy a unique blend of crisp air and sunny afternoons, making January a captivating time to experience Jeju’s natural beauty and charm.
January in Jeju City, South Korea, brings a moderate precipitation amount of 58 mm (2.3 in) over approximately 10 rainy days. This sets the stage for slightly wetter months ahead, as February follows closely with 59 mm (2.3 in) and a similar pattern of rainfall. As spring approaches, March sees a noticeable increase, with precipitation jumping to 101 mm (4.0 in) across 11 days of rain, hinting at the transition to a more dynamic climate. With summer's arrival, the rainfall peaks, particularly in August and September, where monthly totals soar to 197 mm (7.7 in) and 298 mm (11.7 in), respectively. This trend illustrates a distinct seasonal pattern in Jeju, where winter's relative dryness yields to summer's lush, rain-soaked days, making the island a vivid tapestry of climate contrasts throughout the year.
In January, Jeju City experiences a humidity level of 72%, setting the tone for a month that bridges the crispness of winter with the impending onset of spring. This relatively stable humidity slightly declines to 70% in February, before creeping up again to 73% in March, as the surroundings start to awaken with the arrival of spring blooms. A noticeable surge occurs in the following months, with humidity skyrocketing to 83% in April, reaching 89% in May, and peaking at a staggering 98% in July. The summer months are characterized by lush greenery and a tropical atmosphere, but the humidity begins to ease off slightly as autumn approaches, dropping to 84% in September and continuing its descent to 71% by December. Overall, Jeju City’s humidity shows a clear seasonality, highlighting the region's transition from winter tranquility, through vibrant springs and sweltering summers, to the milder autumn and winter months.
In January, Jeju City experiences a moderate UV Index of 4, suggesting a safe exposure level for outdoor activities, with a burn time of about 30 minutes. However, as winter transitions into spring, a noticeable rise in UV levels begins. By February, the Index jumps to 6, categorized as high, and this upward trend continues into March with a UV Index of 7. As the months progress towards summer, the intensity escalates sharply; by April, the Index reaches 9, indicating very high exposure, necessitating more caution, especially during May and June when levels peak at 10 and 11, respectively. The summer months see extreme conditions, with a UV Index of 12 in both July and August. As autumn approaches, the UV Index gradually decreases, settling back to high levels of 6 in November and returning to 4 by December. These trends underscore the importance of UV awareness year-round. To learn more about the UV Index in Jeju City, visit Jeju City UV Index.
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In January, Jeju City experiences 166 hours of sunshine, setting the stage for the year with a gentle start. As winter melds into spring, the days gradually brighten, with February seeing a significant rise to 228 hours. By March, the sunshine hours continue to climb to 267, heralding the approach of warmer months. The trend accelerates into April and May, reaching an impressive 292 and 304 hours respectively, making these months perfect for exploring the island’s natural beauty. Even during the summer, the sun graces Jeju with an impressive 298 hours in both July and August, ensuring vibrant outdoor experiences. As autumn arrives, the sunshine begins to wane, with September and October offering 266 and 268 hours. Despite the decline, November and December retain a respectable 230 and 203 hours, wrapping up a year filled with sunlight. The overall pattern shows a delightful progression, creating an inviting atmosphere in Jeju that beckons visitors throughout the seasons.
In Jeju City, South Korea, the likelihood of sunny weather in January stands at a modest 31%, which sets the stage for a gradual increase in sunshine as the year progresses. Following January, the chances rise to 37% in February and continue to hover around the mid-thirties through March and May. Notably, April marks a peak in sunshine prevalence at 41%, after which the chances dip slightly during the summer months, with July experiencing the least sun at just 24%. As the seasons shift, October emerges as the sunniest month with a striking 56% chance, while November and December also enjoy favorable conditions at 51% and 39%, respectively. This pattern highlights a yearly transition where the weather becomes increasingly favorable for sunshine, particularly in the fall months.
In Jeju City, South Korea, the daylight duration shows a captivating seasonal rhythm throughout the year. In January, residents enjoy 10 hours of daylight, a figure that remains steady through February. As spring approaches in March, the days lengthen to 11 hours, signaling the gradual awakening of nature. The shift becomes more pronounced in April and May, where daylight reaches 13 hours, inviting outdoor exploration. Early summer shines brightly, providing 14 hours of sunlight in both June and July, perfect for beach outings and coastal adventures. However, as summer wanes into August, the daylight starts to recede slightly to 13 hours. September sees a gradual decline to 12 hours, leading into the shorter days of autumn, where October and November settle back to 11 and 10 hours respectively. By December, the sunlight dwindles to 9 hours, ushering in the winter months with their serene calm. This cyclical pattern not only highlights the beauty of Jeju's changing seasons but also enriches the local lifestyle and activities throughout the year.
In January, Jeju City experiences a steady average wind speed of 6.5 m/s (14 mph), repeating this brisk pace from February as well. These months mark the peak of winter winds, gradually giving way to a milder spring. As temperatures rise, March and April see a noticeable dip to 5.0 m/s (11 mph), inviting a breath of fresh air, while May and June settle into even gentler breezes, dropping to 4.1 m/s (9 mph) and 3.3 m/s (7 mph), respectively. This trend continues into the summer months, where the winds fluctuate, reaching 4.7 m/s (10 mph) in July before easing again in August. As autumn arrives, wind speeds pick up slightly in September to 5.6 m/s (13 mph), followed by a gradual decline through October and November. By December, a refreshing return to 6.0 m/s (13 mph) heralds the start of winter once more, framing a captivating cycle of winds that shape Jeju's unique climate.
Weather in Jeju City varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Jeju City, focusing on differences in temperature, rainfall, humidity, and UV levels.
January and February in Jeju City exhibit similar weather patterns, though with slight variations. January typically experiences colder temperatures, with a minimum of -2°C (29°F) and a maximum of 19°C (66°F), while February sees a slightly warmer minimum of -1°C (31°F) and a maximum of 17°C (63°F). Precipitation levels are comparable, with January receiving 58 mm (2.3 in) over 10 days and February totaling 59 mm (2.3 in) over 9 days. Humidity remains relatively high in both months, at 72% for January and 70% for February. For more detailed insights, you can check Jeju City weather in February.
In January, the weather tends to be quite cool, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 19°C (66°F). The average temperature sits at about 6°C (44°F) and there is a moderate level of precipitation, totaling 58 mm (2.3 in) over approximately 10 days, accompanied by a humidity level of 72%.
In contrast, March experiences slightly milder temperatures, with a minimum of 3°C (37°F) and a maximum of 18°C (65°F), resulting in an average temperature of 10°C (51°F). However, it is also wetter, with precipitation reaching 101 mm (4.0 in) across 11 days, and humidity remains similar at 73%. Overall, March generally feels a bit warmer and wetter compared to January. For more details, you can check Jeju City weather in March.
In comparing the weather between January and April, January tends to be cooler with average temperatures ranging from a low of -2°C (29°F) to a high of 19°C (66°F). With precipitation measuring 58 mm (2.3 in) over about 10 days, humidity sits at a moderate 72%. In contrast, April experiences a mild increase in temperatures, with lows of 6°C (43°F) and highs reaching 20°C (69°F), making it generally more pleasant. The month also sees more rainfall, totaling 91 mm (3.6 in) but occurring over fewer days, specifically 7, and with humidity increasing to 83%. For more detailed information, you can refer to Jeju City weather in April.
January and May present contrasting weather patterns. 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 6°C (44°F). The month experiences about 58 mm (2.3 in) of precipitation over 10 days, along with a humidity level of 72%. In stark contrast, May brings warmer temperatures, with nighttime lows of 10°C (51°F) and daytime highs reaching 24°C (75°F), averaging 17°C (63°F). The month sees increased rainfall, totaling 92 mm (3.6 in) over 9 days, and higher humidity at 89%. For more about the weather in May, please visit Jeju City weather in May.
In January, the weather is considerably cooler, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 19°C (66°F) and an average of 6°C (44°F). The month sees moderate precipitation, totaling 58 mm (2.3 in) over about 10 days, along with a humidity level of 72%. In contrast, June brings a much warmer climate, with temperatures starting at a minimum of 16°C (60°F) and reaching a maximum of 26°C (79°F), averaging around 21°C (70°F). This month experiences more rainfall, with a total of 141 mm (5.6 in) also across 10 days but with increased humidity at 93%. For a detailed look at weather specifics, you can visit Jeju City weather in June.
January and July present contrasting weather patterns in Jeju City. In January, temperatures range from a chilly -2°C (29°F) at night to a mild average of 6°C (44°F) during the day, with a maximum of 19°C (66°F). The month is characterized by 58 mm (2.3 in) of precipitation over approximately 10 days and a humidity level of 72%. In stark contrast, July experiences much warmer conditions, with minimum temperatures of 19°C (67°F) and an average of 25°C (77°F), peaking at 31°C (88°F). This summer month brings a significant increase in rainfall, totaling 170 mm (6.7 in) spread across 14 days, coupled with a high humidity level of 98%. For a detailed look at July's climate, check out Jeju City weather in July.
January and August present stark contrasts in weather patterns. 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 6°C (44°F). The month sees about 58 mm (2.3 in) of precipitation over approximately 10 days, coupled with a humidity level of 72%. In contrast, August brings significant warmth, with temperatures ranging from a comfortable 22°C (72°F) to a hot 31°C (88°F), averaging 27°C (81°F). This summer month experiences heavier rainfall, totaling 197 mm (7.7 in) across 15 days, alongside a high humidity level of 96%. For a closer look at the specifics of August's weather, visit Jeju City weather in August.
In comparing the weather between January and September, it's evident that September tends to be significantly warmer and wetter. January features a cooler temperature range, with a minimum of -2°C (29°F) and a maximum of 19°C (66°F), along with an average temperature of 6°C (44°F). In contrast, September boasts a much milder climate, with temperatures ranging from a minimum of 18°C (65°F) to a maximum of 28°C (83°F) and an average of 23°C (74°F). Additionally, September experiences considerably more rainfall, with 298 mm (11.7 in) over 15 days, compared to January’s 58 mm (2.3 in) across 10 days. The humidity also rises in September, reaching 84% compared to January's 72%. For a detailed look at Jeju City's weather specifics in September, visit Jeju City weather in September.
January and October present significantly different weather patterns. In January, temperatures range from a chilly -2°C (29°F) to a mild 19°C (66°F), with an average of 6°C (44°F). The month experiences around 58 mm (2.3 in) of precipitation over 10 days, accompanied by a humidity level of 72%. In contrast, October warms up, with temperatures ranging from a minimum of 11°C (53°F) to a comfortable maximum of 27°C (81°F), averaging 19°C (66°F). Precipitation is higher at 109 mm (4.3 in) but occurs over fewer days, with 9 days of rainfall and a slight increase in humidity to 78%. For more details on October weather, visit Jeju City weather in October.
In January, the weather is noticeably cooler, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 19°C (66°F), and an average of 6°C (44°F). The month experiences a higher amount of precipitation, totaling 58 mm (2.3 in) over about 10 rainy days, accompanied by a humidity level of 72%. In contrast, November offers milder temperatures, with a more pleasant range from 6°C (43°F) to 22°C (71°F), averaging 14°C (57°F). Precipitation in November is lower, at 46 mm (1.8 in) over 7 days, while humidity is slightly higher at 73%. For more detailed information, check out Jeju City weather in November.
In January, temperatures in Jeju City range from a chilly minimum of -2°C (29°F) to a maximum of 19°C (66°F), with an average temperature of 6°C (44°F). In contrast, December offers milder conditions, with a minimum of 0°C (33°F) and a maximum of 20°C (68°F), leading to an average temperature of 9°C (48°F). Both months experience similar precipitation levels, with January receiving 58 mm (2.3 in) and December slightly higher at 61 mm (2.4 in), each seeing rain on about 10 days. Humidity remains relatively stable, with January at 72% and December slightly lower at 71%. For more detailed information, check out Jeju City weather in December.
January in Jeju City presents a unique charm, characterized by cooler temperatures and increased humidity compared to other months. With an average temperature hovering around 6°C, visitors experience a crisp winter atmosphere, occasionally warming to a maximum of 19°C on brighter days. While the island sees about ten days of precipitation, the rain typically adds to the island's lush landscape rather than dampening spirits. Overall, January serves as a refreshing departure from the milder, more humid summer months, making it a distinct time to explore Jeju's natural beauty. For further insights into the dynamics of the weather throughout the year, check out the complete Jeju City Climate guide.