Last updated: August 27, 2025
May in Chiang Mai, Thailand is characterized by warm temperatures and increased humidity. With maximum highs reaching 41°C (106°F), the average temperature settles around a comfortable 30°C (86°F). Nighttime brings some reprieve, with lows of 23°C (73°F). Rainfall begins to make its presence felt, totaling 82 mm (3.2 in) over 9 days, contributing to the lush landscape for which the region is known. Visitors should be prepared for a mix of sunny days and refreshing showers, all set against the backdrop of a vibrant and blossoming environment.
As May rolls into Chiang Mai, the temperatures transition into the warm embrace of early summer, with minimums around 23°C (73°F) and averages peaking at 30°C (86°F). This month sees a slight rise in temperatures from April, where maximums could reach sizzling 41°C (106°F), continuing the trend of higher heat that began in March. The warmth makes May a perfect time for outdoor adventures, although the humidity increases as the month progresses, hinting at the impending rainy season. With lush greenery beginning to re-emerge, May embodies a lively atmosphere, making it a vibrant time to experience this enchanting northern city.
In Chiang Mai, May marks a significant shift in the climate, showcasing a notable increase in precipitation that signals the onset of the rainy season. With an average of 82 mm (3.2 in) of rainfall spread over 9 days, May stands out as the month that prepares the city for the more intense downpours to come in June and July. This month experiences a dramatic rise from April’s 42 mm (1.7 in), underscoring a trend of escalating rainfall as the year progresses. As the dry days of early months fade into history, the lush landscapes of Chiang Mai become vibrant and alive, illustrating nature’s resilience and the region’s transition into a wetter, greener phase.
As the months progress into May, Chiang Mai experiences a notable shift in humidity, rising to 63%. This marks a substantial increase from the drier early months of the year, where January to April saw levels ranging from 36% to 51%. The rising humidity signals the onset of the wet season, with June leading to a steeper climb to 81%, and the peak occurring in August at a staggering 91%. This trend indicates that visitors can expect a marked increase in moisture in the air, transforming the landscape into a lush oasis, albeit with more humid conditions that can impact outdoor activities. Thus, while dry months offer comfortable conditions, May serves as a precursor to the tropical climate that characterizes Chiang Mai in the summer.
In May, Chiang Mai experiences a UV Index of 14, categorizing it as extreme exposure, which means you should limit your time in the sun to just 10 minutes to avoid skin damage. This trend of increasing UV intensity continues from previous months of March and April, both with a UV Index of 13. As summer heats up, the UV levels reach their peak during this time, underscoring the importance of sun protection. With prolonged periods of extreme exposure set through June and July, it's crucial to stay informed about UV safety measures. For more details on the UV Index and how to protect yourself, check out Chiang Mai UV Index.
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May in Chiang Mai, Thailand, offers a delightful embrace of sunshine with an impressive 330 hours of daylight. Following the upward trend from March's 338 hours and April's 321 hours, May maintains this bright momentum, making it one of the sunniest months of the year. This consistency is complemented by a gradual decline as the rainy season approaches, evident in June's drop to 269 hours. The trend highlights Chiang Mai's appeal, where visitors can enjoy abundant sunshine before the lush greenery of the monsoon enhances the landscape. With May's warm temperatures and vibrant sun, it’s the perfect time to explore the city's cultural treasures and natural beauty.
In Chiang Mai, Thailand, the likelihood of sunny weather shows a distinct trend throughout the year. After enjoying high sunshine probabilities from January to April, peaking at 83% in March, May takes a noticeable dip to 45%, signifying the onset of the rainy season. This shift is a stark contrast to the preceding months, where sunshine was almost a guarantee. As temperatures rise and humidity increases, Chiang Mai’s May weather becomes more unpredictable, exhibiting a clear transition into the wet months that follow. By June, the chance of sunny days plummets dramatically to just 12%, illustrating that planning for clear skies in May requires careful consideration for those hoping to catch a gleam of sunshine before the monsoon fully sets in.
As the seasons transition in Chiang Mai, Thailand, so too does the duration of daylight, creating a rhythm to the year. In the early months of January and February, daylight remains consistent at 11 hours, providing a gentle start to the year. March and April see an awakening, with 12 hours of daylight signaling the approach of warmer days. The real transformation occurs in May, when daylight stretches to 13 hours, reaching its peak and continuing through June and July. This abundance of light promotes a vibrant atmosphere as the region basks in longer days. As August arrives, daylight begins a gradual retreat to 12 hours, followed by a further decrease in the autumn months of September and October, returning to 11 hours as the year winds down, capturing the cyclical nature of Chiang Mai's daylight experience.
In May, Chiang Mai experiences a steady average wind speed of 1.3 m/s (3 mph), aligning with the season's gentle breezes. This consistency, shared with January, March, and April, hints at a tranquil transition into the warmer months. As temperatures rise and humidity begins to climb, these mild winds serve as a refreshing reprieve, making outdoor activities more enjoyable. Following May, the wind picks up slightly in June, reaching 1.4 m/s before tapering off again into the quieter months of September and October. Overall, May stands out as a harmonious bridge between the cooler breezy days of early year and the sultry summer winds that follow.
Weather in Chiang Mai varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Chiang Mai, focusing on differences in temperature, rainfall, humidity, and UV levels.
May and January present contrasting weather experiences in Chiang Mai. May boasts significantly higher temperatures, with averages around 30°C (86°F) and peaks reaching up to 41°C (106°F), accompanied by a considerable 82 mm (3.2 in) of precipitation over 9 days, leading to a higher humidity of 63%. In stark contrast, January features a milder climate, with average temperatures of 22°C (72°F) and maximums of 34°C (93°F). This cooler month sees minimal rainfall, just 10 mm (0.4 in) over 2 days, and lower humidity at 51%, making it a much drier period. For more details, check Chiang Mai weather in January.
May and February present strikingly different weather conditions. In May, temperatures are notably higher, with nighttime lows around 23°C (73°F) and daytime averages soaring to 30°C (86°F), reaching peaks of 41°C (106°F). This month also brings increased humidity at 63% and more frequent rainfall, averaging 82 mm (3.2 in) over about 9 days. In contrast, February enjoys milder temperatures, with minimums of 11°C (53°F) and averages of 24°C (75°F), culminating at a maximum of 36°C (97°F). Notably, February experiences virtually no rainfall, with only 2 mm (0.1 in) recorded across the month and lower humidity at 46%. For a more detailed look at the weather in February, check out Chiang Mai weather in February.
In comparing the weather between March and May, March tends to offer cooler temperatures with minimums around 16°C (60°F) and an average of 28°C (82°F), peaking at 40°C (104°F). The month is notable for its dry conditions, recording only 1 mm of precipitation and no rainy days, with humidity levels at a relatively low 38%. In contrast, May experiences a significant rise in temperature, starting at a minimum of 23°C (73°F) and averaging 30°C (86°F), reaching highs of 41°C (106°F). Additionally, May is characterized by increased humidity at 63% and about 82 mm of precipitation spread over 9 days, indicating a more tropical and saturated climate. For more details on March weather, you can visit Chiang Mai weather in March.
In comparing the weather of April and May, it is evident that May experiences slightly higher average temperatures, with a minimum of 23°C (73°F) and an average of 30°C (86°F), compared to April's minimum of 18°C (65°F) and average of 29°C (85°F). However, April sees a slightly higher maximum temperature of 42°C (107°F) compared to May’s maximum of 41°C (106°F). Precipitation in May is significantly higher, with 82 mm (3.2 in) over 9 days, while April has only 42 mm (1.7 in) over 6 days. Additionally, humidity levels rise in May to 63%, compared to April's much lower 36%. For more insights, check out Chiang Mai weather in April.
In comparing the weather patterns of May and June, May typically boasts higher average temperatures, with a range from a minimum of 23°C (73°F) to a maximum of 41°C (106°F), while June sees slightly cooler averages with a maximum of 40°C (104°F). Humidity levels rise from 63% in May to 81% in June, contributing to a more humid atmosphere as summer progresses. Additionally, June experiences greater precipitation, with 145 mm (5.7 in) over 17 days compared to May's 82 mm (3.2 in) across 9 days. For more details, you can check Chiang Mai weather in June.
In May, the weather in Chiang Mai typically features higher average temperatures, peaking at around 30°C (86°F) and reaching a maximum of 41°C (106°F), with a total precipitation of 82 mm (3.2 in) spread over 9 days and humidity at 63%. In contrast, July sees a drop in the average temperature to 28°C (83°F), with the maximum hovering around 40°C (104°F). However, July is significantly wetter, receiving 218 mm (8.6 in) of rainfall over 22 days, resulting in higher humidity at 83%. This shift indicates that while May is hotter, July brings increased rainfall and humidity. For more information on July weather, visit Chiang Mai weather in July.
May experiences warmer temperatures compared to August, with averages around 30°C (86°F) and maximums reaching up to 41°C (106°F). In contrast, August offers a cooler average temperature of 27°C (81°F), with a maximum of 36°C (97°F). However, August is characterized by significantly higher precipitation, totaling 268 mm (10.5 in) over 26 days, compared to May's 82 mm (3.2 in) spread over just 9 days. Additionally, the humidity in August climbs to 91%, making it feel much more oppressive than May's 63%. For further details, check out Chiang Mai weather in August.
May and September present distinct weather patterns in Chiang Mai. May typically boasts warmer temperatures, with minimums around 23°C (73°F) and averaging up to 30°C (86°F), reaching a maximum of 41°C (106°F). In contrast, September features milder temperatures, with a minimum of 22°C (71°F) and an average of 27°C (81°F), peaking at 35°C (95°F). While May has a moderate amount of precipitation at 82 mm (3.2 in) over about 9 days, September sees a significant increase in rainfall, totaling 198 mm (7.8 in) over 21 days, making it one of the wettest months. Additionally, September carries a higher humidity level of 83%, compared to May's 63%. For more detailed insights, refer to Chiang Mai weather in September.
In May, the weather is typically hot, with temperatures ranging from a minimum of 23°C (73°F) to a high of 41°C (106°F) and an average of 30°C (86°F). The month sees around 82 mm (3.2 in) of precipitation over about 9 days, with humidity levels around 63%. In contrast, October experiences milder temperatures, with a minimum of 20°C (69°F), an average of 26°C (80°F), and a maximum of 34°C (94°F). However, it is also wetter, with 156 mm (6.1 in) of rainfall spread over approximately 18 days and slightly higher humidity at 67%. For more specific details on October weather, you can check Chiang Mai weather in October.
May and November offer contrasting weather experiences. In May, temperatures soar with a minimum of 23°C (73°F) and can reach as high as 41°C (106°F), making it notably hotter than in November, where temperatures range from a cooler 13°C (56°F) to a maximum of 34°C (93°F). Additionally, May experiences more precipitation, averaging 82 mm (3.2 in) over about 9 days, while November sees significantly less rainfall at 24 mm (0.9 in) across 5 days. Humidity levels are also slightly higher in May at 63%, compared to 60% in November. For those interested in the specifics of November weather, you can find more information at Chiang Mai weather in November.
May and December offer starkly contrasting weather conditions. In May, temperatures range from a minimum of 23°C (73°F) to a scorching maximum of 41°C (106°F), with an average temperature of 30°C (86°F). The month is also characterized by higher humidity at 63% and significant precipitation, averaging 82 mm (3.2 in) over about 9 days. In contrast, December brings much cooler weather, with a minimum temperature of 6°C (43°F) and an average of 21°C (71°F), peaking at a comfortable 33°C (91°F). Rain is scarce in December, with only 13 mm (0.5 in) of precipitation expected over just one day, and humidity slightly lower at 56%. For those planning to visit, more details can be found at Chiang Mai weather in December.
As May unfolds in Chiang Mai, the transition to the sweltering summer heat becomes noticeable, with temperatures reaching their peak. This month stands out with its higher averages compared to cooler months, painting a vivid picture of warm days and moderately humid evenings. While occasional rains—around nine days of precipitation—bring relief from the heat, the overall climate feels notably warmer and more tropical. If you're eager to learn more about how May’s weather compares to other months, explore the detailed insights available in our guide to the Chiang Mai Climate.