Last updated: August 28, 2025
In May, Ulan Bator, Mongolia, experiences a captivating transition from the chill of winter to the warmth of summer. With maximum temperatures reaching 30°C (87°F) and an average of 9°C (48°F), the month offers a delightful mix of sunny days and crisp evenings. Nights can still be chilly, with temperatures dipping to a minimum of -8°C (18°F). Rainfall is modest, totaling 26 mm (1.0 in) over approximately 5 days, while the humidity remains around 50%, lending a refreshing quality to the atmosphere. This month is perfect for outdoor enthusiasts eager to explore the stunning landscapes of Mongolia as nature awakens in vibrant colors.
In May, Ulaanbaatar begins to shake off the chill of winter, with temperatures showing a significant upward trend. The minimum temperature rises to -8°C (18°F), dramatically warmer than the preceding months, while the average temperature reaches a comfortable 9°C (48°F). As the days lengthen, the city sees maximum temperatures soar to a pleasant 30°C (87°F), making it one of the warmest months of the year. This transition signifies a vibrant awakening in the capital, where the emergence of greenery and outdoor activities become commonplace, inviting both locals and visitors to bask in the growing warmth of spring.
In May, the weather in Ulan Bator, Mongolia marks a significant turning point, as the city receives 26 mm (1.0 in) of precipitation over 5 days—a noticeable increase from the preceding months. This enhancement in rainfall, growing from 15 mm (0.6 in) in April, signals the arrival of warmer and more vibrant spring days. Notably, May's precipitation is crucial for replenishing the dry landscapes as the city transitions towards summer. The gradual rise in rainfall from January's meager 2 mm to June's 44 mm underscores the city's shift into its wetter season, highlighting a trend of increasing moisture that prepares the region for the more substantial rains of summer. As each month progresses, the enhancement in precipitation plays a key role in nurturing the local environment, paving the way for flourishing flora as Ulan Bator basks in the joys of spring.
In Ulan Bator, Mongolia, May marks a notable shift in humidity as it drops to 50%, showcasing the transition into summer. This decrease follows a gradual decline from the frosty January levels of 92%, reflecting the city's shift from the harsh winter months. As spring settles in, humidity levels steadily decrease from 84% in February to 59% by April, indicating a freshening ambiance. After May, humidity begins to rise slightly again in June, reaching 55%, yet remains significantly lower than the winter peaks. This trend suggests that while Ulan Bator enjoys a drier climate in May, the onset of summer brings a gradual return of moisture, setting the stage for a contrasting seasonal experience.
As spring transitions into summer, May marks a significant rise in the UV Index in Ulan Bator, Mongolia, reaching a striking 9—a level classified as very high. This increase signals a notable change from earlier months, where the UV Index was considerably lower, ranging from 2 in January to 7 in April. As the month progresses, residents and visitors should be mindful of their sun exposure, with a burn time of just 15 minutes under clear skies. This trend of elevated UV levels continues into June, July, and August, emphasizing the importance of sun protection during these peak summer months. To prepare effectively, it's essential to stay informed about these changes in UV intensity. For more detailed insights, check Ulan Bator UV Index.
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In Ulan Bator, Mongolia, May heralds a delightful peak in sunshine, boasting an impressive 376 hours of sunlight. This bright month marks a continuation of the upward trend that begins in January, where sunlight hours gradually increase from a modest 203 hours. By the time spring unfolds in May, the city embraces nearly four times the sunlight of its coldest month. This surge in brightness not only signals the arrival of warmer weather but also sets the stage for the lush vibrancy of summer. After May, the sunshine gradually tapers off, yet the city retains a respectable amount through June and July, showcasing the dynamic shifts in daylight that characterize Mongolia’s unique climate.
In Ulan Bator, Mongolia, the likelihood of sunny weather in May holds steady at 45%, reflecting a trend of moderate sunshine as spring transitions into summer. While this percentage is a drop from the sunnier months of February and March, which boast chances of 58% and 55% respectively, it aligns closely with the overall pattern observed in the preceding months of April and the subsequent month of June. Notably, the chance of sunny days sees a gradual decline during the warmer summer months of July and August, marking a shift from the higher probabilities earlier in the year. Consequently, while May offers a fair share of sun, it serves as a reminder that even as temperatures rise, clear skies may not always steal the show.
In Ulan Bator, Mongolia, the transition from winter to summer is beautifully marked by an increase in daylight hours. Beginning with 8 hours in January, the days gradually lengthen, reaching 10 hours by February and peaking at 15 hours in both May and June. This surge in daylight is particularly noticeable as spring unfolds, with the city basking in 13 hours by April. As summer wanes into early autumn, daylight begins to retreat, dropping to 12 hours in September before settling back to 8 hours by December. The rhythm of daylight in Ulan Bator not only signifies seasonal changes but also influences the vibrant life and activities of its residents throughout the year.
In Ulan Bator, May ushers in a noticeable shift in wind patterns as the city transitions into spring. With an average wind speed of 3.8 m/s (9 mph), May is characterized by gentle yet refreshing breezes that surpass the calmer conditions of the earlier months. This upward trend from April's 3.4 m/s (8 mph) signifies not only the arrival of warmer weather but also a time when outdoor activities become more inviting. As the city prepares for summer, the winds in May often invigorate the atmosphere, providing a dynamic backdrop to the rich cultural life of Mongolia’s capital.
Weather in Ulan Bator varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Ulan Bator, focusing on differences in temperature, rainfall, humidity, and UV levels.
The weather in May and January presents a striking contrast in Ulan Bator. May experiences a temperature range from a chilly minimum of -8°C (18°F) to a pleasant maximum of 30°C (87°F), with an average of 9°C (48°F). This month also sees moderate precipitation of 26 mm (1.0 in) over about five days, accompanied by a relatively comfortable humidity of 50%.
In stark contrast, January is much harsher, with temperatures plummeting to a minimum of -42°C (-44°F) and an average of -22°C (-8°F), peaking at only -5°C (23°F). Precipitation is minimal at just 2 mm (0.1 in) spread over zero days, and the air is notably humid at 92%. For a more detailed look at January weather, visit Ulan Bator weather in January.
May and February present strikingly different weather patterns. In May, temperatures range from a minimum of -8°C (18°F) to a maximum of 30°C (87°F), with an average temperature hovering around 9°C (48°F). The month sees a moderate 26 mm (1.0 in) of precipitation over five days and a humidity level of 50%. In stark contrast, February experiences much harsher conditions with temperatures dipping as low as -38°C (-36°F) and averaging -18°C (0°F), only reaching a maximum of 4°C (39°F). Precipitation is minimal, totaling just 5 mm (0.2 in) over a single day, and the humidity remains significantly higher at 84%. For more detailed information, you can visit Ulan Bator weather in February.
When comparing the weather in May and March, it's clear that May experiences a significant warming trend. While March features starkly low temperatures, with averages dipping to -7°C (20°F) and minimums plummeting to -29°C (-20°F), May offers a much more temperate climate, with average highs reaching 9°C (48°F) and maximums soaring to 30°C (87°F). Precipitation levels are also notably different; March sees only 7 mm (0.3 in) over 2 days, whereas May has 26 mm (1.0 in) across roughly 5 days, contributing to a more humid atmosphere at 50% compared to March's 64%. For a closer look at the weather specifics, you can check out Ulan Bator weather in March.
When comparing the weather in April and May, there are noticeable differences in temperature, precipitation, and humidity. In April, temperatures range from a low of -16°C (4°F) to a high of 25°C (77°F), with an average of 2°C (36°F). This month experiences 15 mm (0.6 in) of precipitation over about 4 days, and humidity is relatively high at 59%. In contrast, May offers a broader temperature range, with minimums at -8°C (18°F), averages of 9°C (48°F), and maximums soaring to 30°C (87°F). May sees increased precipitation at 26 mm (1.0 in) spread across 5 days, while humidity decreases slightly to 50%. For more detailed insights, you can check Ulan Bator weather in April.
May and June showcase a noticeable shift in weather patterns. In May, temperatures range from a minimum of -8°C (18°F) to a maximum of 30°C (87°F), with an average temperature of 9°C (48°F). This month experiences relatively low precipitation at 26 mm (1.0 in) over just 5 days, and humidity levels are around 50%. In contrast, June sees a warmer and more humid climate, with temperatures varying from a minimum of -3°C (28°F) to a maximum of 32°C (90°F), resulting in an average of 15°C (59°F). Rainfall increases to 44 mm (1.7 in) across 7 days, and humidity rises slightly to 55%. For more detailed insights, you can check Ulan Bator weather in June.
The weather in May and July displays notable differences in temperature and precipitation patterns. In May, temperatures can dip as low as -8°C (18°F) but also reach a pleasant maximum of 30°C (87°F), with an average of 9°C (48°F). The month sees relatively low precipitation at 26 mm (1.0 in) over about 5 days and maintains a humidity of 50%. In contrast, July presents a milder minimum temperature of 5°C (41°F) and an increased average of 17°C (64°F), with highs peaking at 32°C (91°F). July is also the wetter month, experiencing 72 mm (2.9 in) of rain spread across roughly 12 days and a slightly higher humidity of 57%. For more specific details, you can check Ulan Bator weather in July.
In May, Ulan Bator experiences a broader temperature range with minimums dropping to -8°C (18°F) and maximums soaring up to 30°C (87°F), averaging around 9°C (48°F). The month sees relatively low precipitation at 26 mm (1.0 in) over just 5 days, accompanied by a humidity level of 50%. In contrast, August features a more moderate temperature range, starting from a minimum of 0°C (33°F) and peaking at 28°C (82°F), with an average temperature of 14°C (58°F). However, it is a wetter month, receiving 83 mm (3.3 in) of rain across 13 days and higher humidity at 58%. For more details, you can check Ulan Bator weather in August.
May and September exhibit notable differences in weather patterns. In May, temperatures range from a minimum of -8°C (18°F) to a maximum of 30°C (87°F), with an average of 9°C (48°F), and the month sees comparatively low precipitation at 26 mm (1.0 in) over just 5 days. Conversely, September features slightly cooler temperatures, with a minimum of -9°C (16°F) and a maximum of 27°C (81°F), while maintaining the same average of 9°C (48°F). However, this month experiences more rainfall, accumulating 51 mm (2.0 in) over 8 days, and higher humidity at 65%. For further details, you can refer to Ulan Bator weather in September.
May and October in Ulan Bator present distinct weather patterns that reflect the transition from spring to autumn. In May, temperatures can vary widely, with minimums dropping to -8°C (18°F) and highs reaching up to 30°C (87°F), resulting in a pleasant average of 9°C (48°F). The month sees some precipitation, totaling 26 mm (1.0 in) over about 5 days, with humidity at a moderate 50%. In contrast, October ushers in a much cooler climate, where minimum temperatures plummet to -16°C (4°F) and average temperatures hover around -1°C (30°F), peaking at a milder 22°C (72°F). This month brings slightly less precipitation at 21 mm (0.8 in) over just 4 days, but humidity rises to 65%, creating a crisp atmosphere. For a more detailed look at October's weather, you can check Ulan Bator weather in October.
The contrast between May and November weather is striking, showcasing the significant seasonal changes. In May, temperatures can range from a chilly -8°C (18°F) at night to a warm 30°C (87°F) during the day, with an average of 9°C (48°F). The month experiences moderate precipitation of 26 mm (1.0 in) over about 5 days and maintains a comfortable humidity level of 50%. In stark contrast, November sees much harsher conditions, with nighttime lows plummeting to -35°C (-32°F) and daytime highs barely reaching 9°C (49°F), averaging -12°C (11°F). Precipitation drops to a mere 10 mm (0.4 in) over just 2 days, while humidity rises to 67%. For more detailed information, you can check Ulan Bator weather in November.
May and December present strikingly different weather patterns. In May, temperatures can range dramatically from a frigid -8°C (18°F) to a warm 30°C (87°F), with an average of 9°C (48°F) and a moderate humidity of 50%. Rainfall is also more prevalent during this month, averaging 26 mm over about 5 days. In contrast, December is characterized by severe cold, featuring extreme lows of -39°C (-38°F) and an average temperature of -21°C (-5°F), with a maximum of just -3°C (28°F). The month is notably dry with minimal precipitation of only 3 mm and high humidity at 89%. For more details, refer to the Ulan Bator weather in December.
May in Ulan Bator marks a striking transition into warmer weather, with temperatures rising significantly compared to the chilly preceding months. As the city shakes off the grip of winter, residents and visitors alike can enjoy daytime highs reaching up to 30°C (87°F) while still experiencing the refreshing chill of cooler nights. With average temperatures resting around 9°C (48°F), the weather is much milder than the earlier spring months. While rain is relatively scarce, with only a handful of precipitation days, the moderate humidity at 50% brings a refreshing feel to the vibrant greenery that starts to emerge. For a deeper dive into the climate patterns throughout the year, check out Ulan Bator Climate.