Last updated: October 30, 2025
May in Osan, South Korea is characterized by its warm and inviting climate, with temperatures reaching a maximum of 31°C (89°F) and an average of 18°C (64°F), creating a perfect backdrop for outdoor activities. However, cooler nights can dip to a refreshing minimum of 6°C (42°F). As the month progresses, residents can expect 98 mm (3.9 in) of rainfall spread over 8 days, contributing to the region's lush greenery. With an humidity level of 81%, the air feels pleasantly warm, making May a delightful time to experience the beauty of Osan.
In May, Osan, South Korea, begins to bask in the warmth of spring, showcasing a notable shift in temperatures compared to the colder months. The minimum temperature rises to a mild 6°C (42°F), while the average climbs to a comfortable 18°C (64°F), culminating in a maximum of 31°C (89°F). This spectrum reflects a significant departure from the winter chill, as even April's more moderate temperatures give way to the sun-drenched days of May. As the city transitions into this balmy season, residents and visitors alike can enjoy the blossoming scenery and outdoor activities, signaling the approach of summer's peak heat.
May in Osan, South Korea, marks a significant uptick in precipitation, with rainfall totaling 98 mm (3.9 in) over 8 days. This increase follows a gradual rise from the lighter showers of the earlier months, notably from 54 mm (2.1 in) in April. The month transitions into the wet season, creating a vibrant atmosphere as nature awakens. This trend of heightened rainfall continues into June and July, where Osan experiences some of its heaviest downpours, emphasizing a clear shift towards a humid climate. As the temperatures warm, May serves as a pivotal point, bridging the milder spring weather with the intense summer monsoons.
As spring transitions into summer, May in Osan, South Korea, experiences a notable rise in humidity, peaking at 81%. This increase marks a significant leap from April's 75%, signaling the approach of the sweltering months ahead. The trend continues as June and July see humidity levels soar to 85% and 91%, respectively. Overall, the pattern from January through May reflects a steady climb, hinting at the forthcoming sticky conditions of summer that residents must anticipate. Whether basking in the blooming of spring or bracing for summer’s heat, the humidity levels in Osan shape the city's seasonal character.
As summer approaches, the UV Index in Osan, South Korea, sees a significant rise, especially in May when it reaches 9, categorizing it as very high and resulting in a burn time of just 15 minutes. This upward trend reflects a consistent pattern, with the UV levels steadily increasing from a moderate 3 in January to a peak of 11 in July and August. May's UV Index signals that outdoor enthusiasts need to be particularly cautious about sun exposure, as the preceding months have already hinted at intensifying sunlight. This pattern not only prepares residents for the warmth ahead but also emphasizes the importance of sun safety during these months. For more detailed information on UV levels throughout the year, check Osan UV Index.
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May in Osan, South Korea, is a month that truly shines, boasting 315 hours of sunshine, the highest of the year. This delightful surge follows a steady increase from previous months, where the sunlight steadily grows from 198 hours in January to 289 hours in April. As spring transitions into early summer, the days become longer and sunnier, peaking in May and continuing to shine brightly into June with 318 hours. This trend underscores the region's vibrant seasonal shift, making the outdoor experiences in May especially enjoyable, as locals and visitors alike bask in the warm embrace of the sun before the onset of the slightly cooler months.
In Osan, South Korea, May typically brings a 38% chance of sunny weather, which marks a slight dip compared to the preceding months of January through April, where the likelihood remained above 40%. This decline in sunshine can be seen as a precursor to the summer months, where sunny days become even less frequent, particularly in July and August with their 30% and 31% chances, respectively. Interestingly, as we transition from spring to summer, May's sunlit days are outdone by the rising chances later in the year, particularly in November and December, which boast a 57% and 63% likelihood of clear skies. This trend highlights the unique seasonal shifts in Osan, making each month distinct in its weather patterns.
As May unfolds in Osan, South Korea, residents are greeted with an inviting increase in daylight, extending to 14 hours. This gradual lengthening begins in January with just 9 hours, steadily growing as winter melts into spring. By March, the days stretch to 11 hours, culminating in the vibrant energy of April with 13 hours, which sets the stage for May's delightful brightness. Following the peak in May, daylight remains consistent at 14 hours in both June and July before a gradual decline kicks in with the late summer months. This trend not only enhances the beauty of the season but also invites outdoor activities and social gatherings, making May a truly luminous month in Osan.
In May, Osan experiences mild winds with an average speed of 2.9 m/s (6 mph), mirroring the breezy conditions of April. This gentle transition into late spring features a slight decrease in wind intensity compared to earlier months, as March recorded a higher average of 2.7 m/s (6 mph). As the city heads into the warmer summer months, wind speeds show a gradual decline, with June dropping to 2.2 m/s (5 mph). Overall, May stands out as a stable period, maintaining comfortable wind conditions that accompany the blossoming of spring, while hinting at the calmer days to come in June and July.
Weather in Osan varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Osan, focusing on differences in temperature, rainfall, humidity, and UV levels.
May and January present a stark contrast in weather conditions. In May, temperatures vary significantly, with a minimum of 6°C (42°F), an average of 18°C (64°F), and a maximum reaching up to 31°C (89°F). This month also experiences higher humidity at 81% and more precipitation, totaling 98 mm (3.9 in) over about 8 days. In sharp contrast, January is characterized by much colder temperatures, ranging from a minimum of -17°C (2°F) to a maximum of 13°C (55°F), with an average of -2°C (29°F). The precipitation in January is minimal at just 21 mm (0.8 in) over 2 days and a lower humidity level of 71%. For a detailed look at the weather conditions during this chilly month, check out Osan weather in January.
In comparing the weather patterns of May and February, it's clear that these months present contrasting climates. May enjoys mild temperatures, with an average of 18°C (64°F) and a maximum that can reach up to 31°C (89°F), paired with high humidity at 81%. This month sees roughly 98 mm (3.9 in) of precipitation over about 8 days, contributing to lush spring landscapes. In stark contrast, February experiences much colder conditions, with an average temperature of 0°C (33°F) and a maximum of only 18°C (65°F). The month is characterized by lower humidity at 65% and minimal precipitation, totaling only 23 mm (0.9 in) over just 4 days. For a more detailed look, you can check out Osan weather in February.
When comparing the weather in May to that of March, it's clear that May brings significantly warmer temperatures, with average highs reaching 31°C (89°F) compared to March's maximum of 21°C (70°F). March experiences much cooler conditions, with minimum temperatures dipping as low as -6°C (21°F), while May's minimum temperature is a mild 6°C (42°F). Additionally, May sees a higher level of precipitation at 98 mm (3.9 in) over approximately eight days, in contrast to March's 47 mm (1.9 in) over just five days. Furthermore, the humidity is noticeably higher in May at 81%, compared to 65% in March, contributing to a warmer and more comfortable feel as spring transitions into summer. For those interested in more specific details about the weather in March, you can visit Osan weather in March.
May offers a noticeable warming compared to April, with average temperatures rising from 12°C (54°F) in April to 18°C (64°F) in May. The southern transition into May brings higher maximum temperatures, peaking at 31°C (89°F), compared to April's high of 28°C (82°F). However, May also experiences increased precipitation, totaling 98 mm (3.9 in) over 8 days, in contrast to April's 54 mm (2.1 in) over just 5 days. Additionally, humidity levels are higher in May at 81%, compared to April's 75%. For more detailed information about April weather in Osan, you can visit Osan weather in April.
May and June both offer mild temperatures, but June tends to be warmer overall. In May, temperatures range from a minimum of 6°C (42°F) to a maximum of 31°C (89°F), while June exhibits a broader range, with minimums rising to 12°C (53°F) and maximums reaching 33°C (91°F). Precipitation is slightly lower in June at 80 mm (3.1 in) over 7 days compared to May's 98 mm (3.9 in) over 8 days, but humidity increases slightly from 81% in May to 85% in June. For more detailed weather information, you can check out Osan weather in June.
May and July exhibit notable differences in weather patterns. In May, temperatures range from a cool minimum of 6°C (42°F) to a comfortable average of 18°C (64°F), peaking at 31°C (89°F). The month sees a total precipitation of 98 mm (3.9 in) over about 8 days, with a humidity level of 81%. In contrast, July experiences significantly warmer conditions, with a minimum temperature of 18°C (65°F) and an average of 26°C (79°F), reaching highs of 36°C (98°F). Additionally, July is wetter, accumulating 235 mm (9.3 in) of rainfall over approximately 14 days, accompanied by a higher humidity of 91%. For further details on July's weather, you can check Osan weather in July.
In comparing the weather between May and August, there are notable differences in temperature and precipitation patterns. May typically sees a broader range in temperature, ranging from a cooler minimum of 6°C (42°F) to a warm maximum of 31°C (89°F), with an average of 18°C (64°F). However, it has relatively lower precipitation levels, averaging 98 mm (3.9 in) over about 8 rainy days and a humidity of 81%.
In contrast, August experiences significantly warmer temperatures, with minimums around 16°C (61°F), averages reaching 27°C (80°F), and maximums peaking at a sweltering 38°C (101°F). It also tends to be much wetter, accumulating 255 mm (10.1 in) of rain over 14 days, alongside higher humidity levels at 91%. For more detailed information, check out Osan weather in August.
May and September offer distinctly different weather experiences. In May, temperatures range from a cool minimum of 6°C (42°F) to a warm maximum of 31°C (89°F), with an average of 18°C (64°F). This month tends to be quite humid, with a humidity level of 81%, and experiences around 98 mm (3.9 in) of precipitation over approximately 8 days. In contrast, September features slightly milder minimum temperatures at 9°C (48°F) and an average of 22°C (71°F), while max temperatures remain similar at 31°C (88°F). Although September is marked by a bit more rainfall, totaling 136 mm (5.4 in) over 9 days, the humidity decreases to 77%. For those interested in learning more about the weather specifics during September, you can visit Osan weather in September.
In May, the weather tends to be warmer, with average temperatures reaching around 18°C (64°F) and highs peaking at 31°C (89°F). This month experiences relatively high humidity levels at 81% and receives about 98 mm (3.9 in) of precipitation over an average of 8 days. In contrast, October sees cooler temperatures, with an average of 15°C (59°F) and a maximum of 29°C (84°F), along with lower humidity at 79%. Precipitation is also reduced in October, totaling 62 mm (2.5 in) over just 5 days. For more detailed information on the specific conditions you can expect, visit Osan weather in October.
May and November present notably different weather patterns. In May, temperatures exhibit a wide range, with minimums around 6°C and maximums soaring up to 31°C, averaging a pleasant 18°C. The month also sees higher precipitation levels, totaling 98 mm over approximately 8 days, accompanied by high humidity at 81%.
In contrast, November experiences cooler temperatures, with lows dipping to -5°C and averages around 8°C, peaking at 21°C. Precipitation is less frequent in November, accumulating to 54 mm over just 5 days, while humidity remains fairly consistent at 80%. For more specific insights into the November climate, you can visit Osan weather in November.
May and December present starkly contrasting weather conditions. In May, temperatures range from a mild 6°C (42°F) at night to a warm 31°C (89°F) during the day, with an average of 18°C (64°F). The month is characterized by higher humidity at 81% and a significant amount of precipitation, totaling 98 mm (3.9 in) over approximately 8 days. In contrast, December brings much chillier weather, with temperatures dipping to a minimum of -14°C (8°F) and an average of 0°C (33°F). Daytime highs reach up to 13°C (56°F), while the month is much drier, receiving only 26 mm (1.0 in) of precipitation over about 5 days and exhibiting lower humidity levels at 74%. For a detailed look at what to expect during this cold month, check out Osan weather in December.
As May unfolds in Osan, the weather shifts significantly from the cooler months, bringing a delightful crescendo of warmth and life. With average temperatures rising and featuring maximum highs often reaching into the low 30s °C, outdoor activities become increasingly inviting. Although May sees higher humidity levels and a fair share of precipitation days, the overall climate is marked by a refreshing vibrancy that distinguishes it from the preceding spring months. This transition not only rejuvenates the landscape but also sets the stage for the forthcoming summer. For a deeper dive into the weather patterns throughout the year, explore the detailed insights in Osan Climate.