May Weather in Ulsan, South Korea

Last updated: October 30, 2025

May in Ulsan, South Korea, offers a delightful transition into summer with maximum temperatures soaring up to 33°C (92°F) and an average of 19°C (66°F). While the month showcases warm days, it also experiences cooler nights, with minimum temperatures dropping to 6°C (43°F). Ulsan receives an average of 80 mm (3.1 in) of precipitation over approximately 8 days, contributing to the region’s lush landscape. The humidity remains notably high at 83%, creating a vibrantly lush yet comfortable atmosphere that characterizes the beauty of spring in this coastal city.

May Temperature in Ulsan

In May, Ulsan, South Korea, experiences a delightful transition into warmer weather, with temperatures rising significantly from the cooler months. The month starts with a minimum of 6°C (43°F) and reaches an average of 19°C (66°F), peaking at a warm 33°C (92°F). This substantial increase from April’s mild influence suggests that spring is firmly in place, inviting residents and visitors alike to enjoy outdoor activities. As Ulsan prepares for the impending summer heat in June, May serves as a perfect time to bask in pleasantly warm days, making it a popular month for festivals and coastal excursions. The rising temperatures are not just a numerical trend; they also mark the blooming of vibrant landscapes that captivate the eye and invigorate the spirit.

May Weather in Ulsan: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Ulsan, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Ulsan, May typically has an average temperature of 19°C (66°F), with highs reaching up to 33°C (92°F) and lows dropping to around 6°C (43°F).
JanFebMarAprMayJunJulAugSepOctNovDec374049576671788172635239
Data source: Temperature data for Ulsan generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Ulsan

In May, Ulsan experiences a substantial shift in precipitation patterns, receiving 80 mm (3.1 in) of rain over 8 days. This amount showcases a continuation of the wetter trend observed since March, maintaining similar levels to April's rainfall. As spring transitions toward summer, May's precipitation lays the groundwork for the more intense rainfalls of June and July, indicating an increasing likelihood of monsoon patterns in the region. The frequency of rainy days remains steady compared to previous months, suggesting that while May is not the wettest month, it plays a crucial role in the gradual escalation of Ulsan's wet season.

May Precipitation Trends in Ulsan

The chart displays monthly precipitation patterns in Ulsan, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Ulsan, May typically receives around 80 mm (3.1 inches) of precipitation spread over approximately 8 days.
JanFebMarAprMayJunJulAugSepOctNovDec32398687801442441992361002123
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Ulsan

May marks a notable shift in Ulsan's climate as humidity climbs to a significant 83%, setting the stage for the sweltering months ahead. This increase follows a 75% reading in April, indicating a trend of rising humidity as spring gives way to summer. The jump in moisture levels foreshadows the even more pronounced dampness of June at 87%, creating a stark contrast to the drier winter months. As the year progresses, Ulsan’s humidity consistently elevates, peaking in July with a staggering 95%. This steady escalation highlights the transition into a humid summer, characteristic of the region’s climate.

May Average Humidity in Ulsan

This chart illustrates the average monthly humidity levels in Ulsan, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Ulsan is approximately 83%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec73%67%65%75%83%87%95%93%80%77%75%73%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Ulsan

In May, Ulsan experiences a very high UV Index of 10, matching the level seen in April, which prompts significant caution for outdoor activities. With a burn time of just 15 minutes, it's essential to take protective measures such as wearing sunscreen, hats, and UV-blocking clothing to prevent skin damage. This intensity is a precursor to an even higher UV Index in June, indicating a trend of escalating sun exposure as summer approaches. As daylight hours increase, so does the need for vigilance against harmful rays; thus, understanding these trends can help residents and visitors alike enjoy the beautiful weather while staying safe. For more details, check out the Ulsan UV Index.

Maximum UV Index Levels in Ulsan for May

The chart shows the monthly maximum UV Index (UVI) for Ulsan in May, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In May, the maximum UV index in Ulsan typically reaches 10, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec357101011121210753
Data source: Ulsan May UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

May Sunshine in Ulsan

May shines brightly in Ulsan, South Korea, marking a peak in sunshine with 307 hours of radiant daylight. This month stands out against the backdrop of the year, showcasing a steady increase from 197 hours in January to its dazzling springtime height. Following May, the sunshine remains generous into June with 306 hours, but begins to taper off in the summer months, illustrating a slight decline as July offers 283 hours. Despite this decrease, the overall trend towards longer, sunnier days during the spring months creates a vibrant atmosphere, inviting both locals and visitors to bask in Ulsan's refreshing warmth before the gradual return of the shorter daylight hours in autumn.

Monthly Sunshine Duration in Ulsan: May Highlighted

The May sunshine duration represents the total number of hours Ulsan experiences direct sunlight during the month of May, excluding cloudy or obstructed periods. This chart compares the sunshine duration of May with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec197h242h272h284h307h306h283h299h248h259h238h244h
Data source: Ulsan May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Ulsan During May

In Ulsan, South Korea, the likelihood of sunny weather in May hovers at 38%, which aligns with a noticeable dip that trends from the warmer spring months. After a slight increase in sunshine chances through April (44%), May sees a return to lower probabilities, following the seasonal pattern of decreasing sunlight as summer approaches. This trend continues into the summer months of June and July, where the chances of sun plummet to 27% and 20% respectively. Notably, the likelihood of sunshine dramatically rises again in the fall, with months like November enjoying a brighter 70% chance. Overall, while May offers a fair amount of sunshine, it reflects both seasonal shifts and a transition towards the less sunny summer months.

Percentage of Sunny Days in May in Ulsan

The chart illustrates the percentage of sunny days in Ulsan throughout the year, with May highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Ulsan experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec61%58%38%44%39%27%20%24%28%52%70%77%
Data source: Ulsan May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Ulsan in May

In Ulsan, South Korea, the progression of daylight throughout the year reveals a distinct pattern that reflects the changing seasons. Starting with 10 hours of daylight in both January and February, there’s a noticeable increase as the days gradually lengthen; by March, daylight extends to 11 hours. The real transformation occurs in April, where daylight jumps to 13 hours, signaling the arrival of spring. May brings further warmth and brightness with 14 hours of daylight, a peak that persists through June and July. As summer wanes into August, the days start to shorten slightly to 13 hours, followed by a gradual decrease in September as daylight reaches 12 hours. This declining trend continues into the fall months, where October and November each offer 11 and 10 hours respectively, before dwindling to just 9 hours in December. This rhythm of longer days in the warmer months contrasted by shorter winter days creates a vibrant contrast that defines Ulsan’s yearly cycle.

Average Daylight Hours in Ulsan for May

The chart illustrates the variation in daylight duration in Ulsan throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 3m10h 53m11h 58m13h 5m14h 1m14h 29m14h 15m13h 26m12h 22m11h 15m10h 17m9h 47m
Data source: Ulsan daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Ulsan

In May, Ulsan experiences a gentle average wind speed of 3.0 m/s (7 mph), marking a transition as the spring blooms into summer. This slight decrease from the preceding months reflects a trend of diminishing winds typical for this time of year, where the bustling energy of spring begins to merge with the warmth of summer. As the months progress, June and July see even lower wind speeds, averaging around 2.6 to 2.8 m/s, hinting at a more tranquil atmosphere. However, as autumn approaches in September, the winds pick up again, suggesting a dynamic shift in Ulsan's climate throughout the year. Overall, May's mild breezes create a delightful backdrop for outdoor activities as the region gears up for warmer days ahead.

Average May Wind Speed in Ulsan

The chart displays monthly wind speed patterns in Ulsan, with values for each month shown alongside May's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how May's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.83.83.33.33.0 m/s2.62.82.93.62.93.13.7
Data source: Ulsan May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Ulsan Compares to Other Months

Weather in Ulsan varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Ulsan, focusing on differences in temperature, rainfall, humidity, and UV levels.

When comparing the weather in May and January, it's clear that they offer vastly different climates. May experiences mild to warm temperatures, with averages around 19°C (66°F) and highs reaching up to 33°C (92°F), accompanied by relatively high humidity at 83%. In contrast, January is much colder, with minimum temperatures plummeting to -12°C (11°F) and an average of just 3°C (37°F). Additionally, January has significantly less precipitation, amounting to 32 mm (1.2 in) over only 3 days, compared to May's 80 mm (3.1 in) over 8 days. For more details on January's climate, you can check Ulsan weather in January.

May and February present two distinct climatic experiences. In May, temperatures range from a chilly minimum of 6°C (43°F) to a warm maximum of 33°C (92°F), with an average of 19°C (66°F). The month sees approximately 80 mm (3.1 in) of precipitation over 8 days, coupled with high humidity levels averaging 83%. In contrast, February is much cooler, with temperatures ranging from a minimum of -9°C (15°F) to a maximum of 23°C (73°F) and an average temperature of just 4°C (40°F). It experiences lower precipitation of about 39 mm (1.5 in) over 4 days and lower humidity at 67%. For more details on February weather, check Ulsan weather in February.

In comparing the weather between March and May, it's evident that May brings significantly warmer temperatures, with an average of 19°C (66°F) and a maximum reaching up to 33°C (92°F), in contrast to March's average of 9°C (49°F) and maximum of 22°C (73°F). While both months experience similar levels of precipitation, with March receiving 86 mm (3.4 in) and May slightly less at 80 mm (3.1 in), May's humidity is considerably higher at 83%, compared to March's 65%. This makes May feel warmer and more tropical, while March tends to be cooler and drier. For more detailed insights, you can visit Ulsan weather in March.

May generally offers warmer temperatures compared to April, with minimums rising from 2°C (35°F) in April to 6°C (43°F) in May, and average highs increasing from 26°C (80°F) to 33°C (92°F). However, while May enjoys higher temperatures, it also brings slightly more precipitation, with 80 mm (3.1 in) falling over 8 days, compared to April's 87 mm (3.4 in) over 7 days. Additionally, May has higher humidity levels, averaging 83% compared to April’s 75%. For more detailed insights into April’s weather patterns, you can refer to Ulsan weather in April.

May and June present a transition in weather patterns, with June generally being warmer and more humid. In May, temperatures range from a minimum of 6°C (43°F) to a maximum of 33°C (92°F), with an average of 19°C (66°F). The month sees about 80 mm (3.1 in) of precipitation over 8 rainy days, maintaining humidity levels around 83%. In contrast, June offers a milder temperature range, with a minimum of 13°C (56°F), an average of 22°C (72°F), and a maximum of 32°C (90°F). Rainfall increases significantly to 144 mm (5.7 in) across 10 days, accompanied by a slight rise in humidity to 87%. For more detailed information, check out Ulsan weather in June.

May and July exhibit distinctly different weather patterns. In May, temperatures range from a cool minimum of 6°C (43°F) to a pleasant average of 19°C (66°F), with maximum highs reaching 33°C (92°F). The month experiences a moderate amount of rainfall, totaling 80 mm (3.1 in) over about 8 days, with humidity averaging 83%. In contrast, July sees a significant increase in both temperature and precipitation. Minimum temperatures rise to 17°C (63°F) and average around 26°C (78°F), with maximums peaking at 36°C (98°F). This month is characterized by much heavier rainfall, accumulating 244 mm (9.6 in) across 14 days, and humidity levels soar to 95%. For more details, check out Ulsan weather in July.

In comparing the weather between May and August, we see notable differences in temperature and precipitation. May typically experiences a minimum temperature of 6°C (43°F) and an average high of 33°C (92°F), with an overall average of 19°C (66°F). This month sees about 80 mm (3.1 in) of rainfall over approximately 8 days, with humidity levels averaging 83%.

In contrast, August is warmer, with minimum temperatures starting at 19°C (66°F) and soaring to a maximum of 36°C (98°F), resulting in an average temperature of 27°C (81°F). However, it is also wetter, receiving 199 mm (7.8 in) of precipitation over about 15 days and higher humidity levels at 93%. For a more detailed look at August weather, you can check Ulsan weather in August.

In May, the weather begins to warm up, with temperatures ranging from a brisk 6°C (43°F) at night to a warm 33°C (92°F) during the day, averaging around 19°C (66°F). The month experiences around 80 mm of rainfall over 8 days, and humidity levels sit at a relatively high 83%. In contrast, September tends to be slightly cooler and more humid, with temperatures ranging from a minimum of 13°C (56°F) to a maximum of 30°C (87°F) and an average of 22°C (73°F). However, it is marked by significantly higher precipitation, totaling 236 mm over 12 days. This shift in weather patterns highlights the transition from late spring warmth to early autumn moisture. For more detailed information, you can check Ulsan weather in September.

May and October offer a transition in weather patterns, with May showcasing warmer temperatures and higher humidity. In May, temperatures range from a minimum of 6°C (43°F) to a maximum of 33°C (92°F), with an average of 19°C (66°F), while October features a slightly cooler temperature range from 5°C (41°F) to 30°C (85°F), averaging 17°C (63°F). Precipitation is more pronounced in October, totaling 100 mm (3.9 in) over 7 days, compared to May’s 80 mm (3.1 in) spread across 8 days. Despite the increased rain in October, the humidity is lower at 77%, compared to May's 83%. For more details, check Ulsan weather in October.

May and November showcase strikingly different weather patterns. In May, temperatures range from a chilly 6°C (43°F) at night to a warm 33°C (92°F) during the day, with an average of 19°C (66°F). This month experiences significant humidity at 83% and about 80 mm (3.1 in) of precipitation over approximately 8 days. In contrast, November brings a sharp drop in temperatures, with lows of -2°C (29°F) and daytime highs averaging at 22°C (72°F), resulting in an overall average of 11°C (52°F). This month is much drier, with only 21 mm (0.8 in) of rain over 3 days and a humidity level of 75%. For more detailed insights, check out Ulsan weather in November.

In May, the weather is warm and often fluctuates, with temperatures ranging from a cool minimum of 6°C (43°F) to a scorching maximum of 33°C (92°F). This month experiences an average temperature of 19°C (66°F), accompanied by 80 mm (3.1 in) of precipitation over about 8 days, and high humidity at 83%. In contrast, December brings a much colder climate, with temperatures dropping to a minimum of -9°C (17°F) and an average of just 4°C (40°F). The highest temperature recorded in December reaches 18°C (64°F), and the month sees significantly less rainfall at 23 mm (0.9 in) over just 3 days, along with lower humidity at 73%. For more detailed information, you can check Ulsan weather in December.

Compare Ulsan's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Ulsan

As May unfolds in Ulsan, the weather embraces the full spectrum of spring, painting a vibrant contrast to the cooler months that precede it. Temperatures begin to rise significantly, providing a warm backdrop with an average that leans towards the idyllic, though early mornings and nights still hint at the lingering freshness of spring. With humidity at its peak and occasional rain showers gracing the month, May emerges as a transitional period, inviting residents and visitors alike to relish in the lush greenery and blooming landscapes. This dynamic weather sets the stage for the summer months ahead, making it an opportune time for outdoor adventures. For further insights into Ulsan's weather patterns, visit Ulsan Climate.