Last updated: October 30, 2025
May in Seoul, South Korea showcases a delightful spectrum of weather, with maximum temperatures reaching up to 32°C (89°F), ideal for outdoor activities. The average temperature settles at a comfortable 18°C (64°F), while the evenings can be refreshing with a minimum of 6°C (43°F). However, don't forget your umbrella! The city experiences about 111 mm (4.4 in) of precipitation over 9 days, contributing to the lush greenery of spring. Coupled with a humidity level of 81%, May's climate is a vibrant blend of warmth and refreshing rain, perfect for exploring Seoul's captivating landscapes.
In May, Seoul transforms into a vibrant tapestry of warmth and color, with temperatures significantly rising as spring peaks. The minimum temperature hovers around a comfortable 6°C (43°F), while the average settles at a pleasant 18°C (64°F), paving the way for delightful outdoor activities. With maximums reaching up to 32°C (89°F), the city beckons residents and visitors alike to enjoy its parks and bustling streets. This month marks a striking transition from the chill of winter, reflecting a clear upward trend in temperatures since the cooler days of January, where minima dipped to a biting -18°C (1°F). As the warm days of May give way to the sultry summer months of June and July, Seoul's climate becomes more inviting, solidifying its reputation as a fantastic spring destination.
In May, Seoul experiences a significant uptick in precipitation, with a notable 111 mm (4.4 in) of rainfall across 9 days. This marks a sharp increase from the preceding months, particularly April, which saw only 55 mm (2.2 in) over 6 days. The rise in precipitation not only underscores the transition into the wetter summer season but also indicates that May is a month of heightened rainfall activity compared to the year's earlier months. As lush greenery emerges throughout the city, the abundant rainfall contributes to the vibrant blooms often associated with late spring in South Korea. Such shifts in weather lay the groundwork for the even heavier downpours that characterize the following summer months, setting the stage for the dramatic rainfall patterns typical of July and August.
In May, the humidity in Seoul, South Korea, typically reaches 81%, marking a notable increase as the city transitions into the summer months. This rise from 75% in April signals the onset of the more humid season, as June and July follow with even higher levels, peaking at 85% and 91%, respectively. Notably, the progression from spring to summer exhibits a consistent upward trend in humidity, creating a warm, often muggy environment that characterizes daily life during this time. As temperatures rise, the increasing humidity not only affects comfort levels but also invigorates the lush greenery that Seoul is revered for, making May a vibrant month in the city’s seasonal cycle.
As May unfolds in Seoul, the UV Index reaches a striking 9, indicating a very high level of ultraviolet radiation. This marks a notable increase from the previous months, where the exposure was moderate to high, with January through April showing indices between 3 and 8. With the burn time dropping to just 15 minutes, it’s crucial for residents and visitors alike to take sun safety seriously. This trend continues into June, where the UV Index escalates further to 10, pushing the need for protective measures even higher as summer approaches. For those planning outdoor activities, understanding the risks associated with such high UV levels is essential—stay informed by checking the Seoul UV Index for updates.
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May brings a vibrant burst of sunshine to Seoul, South Korea, with an impressive 311 hours of sunlight. This marks a delightful peak in daylight hours as spring transitions into summer, showcasing an upward trend from 287 hours in April. As the days grow longer, residents and visitors alike can bask in the warmth and enjoy the blossoming surroundings. The momentum continues into June, which boasts slightly more sunshine at 317 hours, emphasizing a sun-drenched season ahead. Overall, May serves as a pivotal moment in Seoul’s climatic calendar, welcoming the radiant joy of summer while gently nudging out the remnants of spring.
In May, the chance of sunny weather in Seoul, South Korea, dips to 37%, marking a noticeable decline from the previous months. This decrease follows a trend of gradually lower sunshine probabilities as spring transitions into summer; while January and February bask in a 55% chance of sun, by the time April rolls around, it only slightly holds at 44%. This pattern suggests that as the region approaches hotter months, overcast days may become more frequent, leading to June's even lower 36% likelihood. Therefore, if you're planning outdoor activities in May, it may be wise to prepare for some cloudy skies amidst your sunlit pursuits.
In Seoul, South Korea, the transformation of daylight duration from January to May paints a beautiful picture of spring’s arrival. Starting with a modest 9 hours in January, daylight gradually increases, gaining an hour each month until it reaches a vibrant 14 hours in both May and June. This steady climb signifies the transition from the cold, dark winter to the warmth and life of spring. As May approaches, the longer days invite residents to embrace the outdoors, making it a time of rejuvenation and celebration. Following May, a subtle decline begins, but the lingering warmth of daylight throughout summer continues the momentum of this beautiful seasonal shift.
As May blossoms in Seoul, South Korea, the average wind speed settles at a gentle 2.6 m/s (6 mph), making it a refreshing month for outdoor activities. This slight dip from April's 2.7 m/s suggests a calming shift as the city transitions into late spring. Following a trend seen throughout the year, the wind speeds are generally mild, with January reaching a peak of 2.8 m/s, and gradually decreasing into the summer months, where July sees the lowest at 1.8 m/s. Such variability hints at a comforting, tranquil atmosphere in May, perfect for enjoying the vibrant cityscape and blooming nature without the overwhelming gusts of stronger winds. As the season advances, residents can appreciate the moderate breezes that accompany the warmer days, setting the stage for a delightful summer ahead.
Weather in Seoul varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Seoul, focusing on differences in temperature, rainfall, humidity, and UV levels.
May and January present stark contrasts in weather. In May, temperatures range from a brisk 6°C (43°F) to a warm 32°C (89°F), with an average temperature of 18°C (64°F). This month also experiences considerable precipitation, totaling 111 mm (4.4 in) over about 9 days, and a high humidity level of 81%. In contrast, January brings a chilly atmosphere with temperatures dipping between -18°C (1°F) and a maximum of 13°C (55°F), averaging -2°C (28°F). Precipitation is minimal at 19 mm (0.8 in) across merely 2 days, and humidity is lower at 71%. This comparison highlights the vibrant warmth of May against the cold, stark chill of January. For more detailed information, check out Seoul weather in January.
May and February present stark contrasts in weather conditions. In May, temperatures range from a chilly minimum of 6°C (43°F) to a warm maximum of 32°C (89°F), with an average of 18°C (64°F). The month sees a significant amount of precipitation, totaling 111 mm (4.4 in) across about 9 days, coupled with high humidity levels at 81%. In contrast, February experiences much colder temperatures, with a minimum of -14°C (7°F) and a maximum of 18°C (65°F), averaging around 0°C (32°F). Precipitation in February is considerably lower, at only 22 mm (0.8 in) over about 4 days, with a lower humidity of 65%. For more details, you can refer to Seoul weather in February.
May weather in Seoul is significantly warmer than in March, with average temperatures ranging from a minimum of 6°C (43°F) to a maximum of 32°C (89°F), compared to March's range of -7°C (20°F) to 21°C (70°F). Additionally, May sees higher precipitation at 111 mm (4.4 in) over 9 days, while March has only 46 mm (1.8 in) spread across 5 days. The humidity also rises in May to 81%, compared to March's 65%, making the weather feel much more humid and warm as spring fully sets in. For more detailed information on March's weather, visit Seoul weather in March.
In comparing the weather of May and April, it becomes clear that May is generally warmer and wetter. While April's temperatures range from a minimum of 0°C (32°F) to a maximum of 28°C (82°F), May presents a broader range with lows of 6°C (43°F) and highs reaching 32°C (89°F), offering an average temperature increase to 18°C (64°F). The month of May also sees a significant uptick in precipitation, totaling 111 mm (4.4 in) over 9 days, compared to April's 55 mm (2.2 in) over just 6 days. Furthermore, humidity levels rise slightly in May to 81%, up from April's 75%. For more detailed insights into April's weather, check out Seoul weather in April.
May and June present a noticeable transition in weather. In May, temperatures range from a cool 6°C (43°F) at night to a warm 32°C (89°F) during the day, with an average temperature of 18°C (64°F). This month also sees significant rainfall, with 111 mm (4.4 in) over 9 days and humidity levels at 81%. In contrast, June experiences warmer nights with a minimum temperature of 12°C (54°F) and can heat up to a maximum of 35°C (94°F), averaging 22°C (72°F). Although June has less rainfall, at 86 mm (3.4 in) over 8 days, humidity slightly rises to 85%. For more detailed information, you can check Seoul weather in June.
May and July present distinct weather patterns that highlight the transition into summer. In May, temperatures range from a minimum of 6°C (43°F) to a maximum of 32°C (89°F), with an average of 18°C (64°F). This month typically experiences 111 mm (4.4 in) of precipitation over about 9 days, accompanied by a humidity level of 81%. In contrast, July sees warmer temperatures, with a minimum of 18°C (64°F), an average of 26°C (79°F), and a peak temperature of 36°C (97°F). The rainfall also increases significantly to 252 mm (9.9 in) spread over 15 days, coupled with a higher humidity of 91%. These factors contribute to a distinctly more humid and wetter July. For more detailed climate information, you can visit Seoul weather in July.
In May, the weather sees a moderate range of temperatures, with a minimum of 6°C (43°F) and a maximum of 32°C (89°F). The average temperature settles at a comfortable 18°C (64°F), accompanied by 111 mm (4.4 in) of precipitation over about 9 rainy days and a humidity level of 81%. In contrast, August experiences a significant increase in both temperature and humidity. The minimum temperature rises to 16°C (61°F), while the maximum can reach up to 38°C (101°F), resulting in an average of 26°C (80°F). Additionally, August is much wetter, with precipitation totaling 269 mm (10.6 in) across 16 days and a humidity level that increases slightly to 91%. For further details, you can check Seoul weather in August.
May and September present a contrasting yet pleasant transition into warmer months in terms of weather. In May, temperatures range from a minimum of 6°C (43°F) to a maximum of 32°C (89°F), with an average of 18°C (64°F) and relatively high humidity at 81%. The month brings about 111 mm (4.4 in) of precipitation over approximately 9 days. By September, the weather shifts slightly warmer, with minimum temperatures at 10°C (50°F) and an average of 21°C (70°F), while still peaking at 31°C (88°F). Precipitation increases to 133 mm (5.2 in), also spread over 9 days, but humidity decreases to 77%. For more details on September weather, you can check Seoul weather in September.
May and October present contrasting weather patterns, highlighting the transition from spring to autumn. In May, temperatures range from a minimum of 6°C (43°F) to a maximum of 32°C (89°F), with an average of 18°C (64°F). This month experiences higher precipitation, totaling 111 mm (4.4 in) over about 9 days, and humidity levels are relatively high at 81%. In contrast, October features cooler temperatures, with a minimum of 0°C (32°F) and an average of 14°C (58°F), peaking at 28°C (83°F). The month is drier than May, with only 63 mm (2.5 in) of precipitation recorded over approximately 6 days and slightly lower humidity at 79%. For more details, check out Seoul weather in October.
May and November present contrasting weather conditions that highlight the transition between spring and late autumn. In May, temperatures range significantly from a minimum of 6°C (43°F) to a maximum of 32°C (89°F), with an average of 18°C (64°F). This month experiences higher humidity at 81% and more rainfall, totaling 111 mm over about 9 days. In contrast, November's temperatures are much cooler, with a minimum of -7°C (21°F) and an average of just 7°C (45°F), peaking at 21°C (70°F). Rainfall is also reduced in November, totaling 54 mm over approximately 5 days, and humidity remains relatively constant at 80%. For more specific details on November weather in Seoul, visit Seoul weather in November.
May and December showcase stark contrasts in weather conditions. In May, temperatures range from a cool 6°C (43°F) at night to a warm 32°C (89°F) during the day, with an average of 18°C (64°F). This month experiences higher humidity at 81% and more precipitation, totaling 111 mm (4.4 in) over about 9 days. In contrast, December brings frigid temperatures, with nighttime lows dropping to -15°C (5°F) and daytime highs reaching only up to 12°C (54°F), resulting in an average temperature of -1°C (31°F). Precipitation is much lower at 22 mm (0.9 in) for just 4 days, and humidity falls to 74%. For more detailed insights on the winter climate, you can check Seoul weather in December.
As spring transitions into summer, May in Seoul brings a delightful mix of warmth and humidity that sets it apart from the cooler months preceding it. With average temperatures rising significantly, the city transforms under the gentle embrace of nature in bloom, although occasional rain showers can add a refreshing contrast. This month strikes a balance between pleasant days and the anticipation of summer heat, as the increased humidity can sometimes feel intense. If you’re curious about Seoul’s year-round weather variations, check out Seoul Climate for a deeper dive into the city's climatological patterns.