Last updated: August 28, 2025
May in Ha Long, Vietnam, presents a dynamic climate marked by warm temperatures and significant humidity. With maximums reaching 36°C (98°F), the island enjoys an average temperature of 27°C (81°F), creating a tropical experience for visitors. However, the allure of this picturesque destination comes with a noteworthy precipitation level of 184 mm (7.2 in), occurring over 19 days throughout the month. The average humidity lingers around 73%, contributing to the lush, vibrant landscapes that Ha Long is famous for. Travelers should be prepared for both sunny excursions and refreshing rain, making May a unique time to explore this breathtaking region.
By May, Ha Long, Vietnam begins to experience a noticeable rise in temperatures, marking the transition to a warmer season. The minimum temperatures start at a mild 19°C (66°F), while the averages climb to a lush 27°C (81°F), peaking at a sizzling 36°C (98°F). This month stands out with significantly warmer conditions compared to the preceding months, as April's maximums lingered around 33°C (91°F). As the days grow longer and the sun's intensity increases, May presents an inviting atmosphere for exploring Ha Long's stunning scenery, although the heat may prompt visitors to seek shade or stay hydrated. With such warmth, May heralds the onset of summer, making it an ideal time to savor the natural beauty of this breathtaking region.
In May, Ha Long, Vietnam experiences a significant surge in rainfall, with total precipitation reaching a notable 184 mm (7.2 in) over 19 days. This marks a sharp increase from the preceding months, particularly when compared to April's 91 mm. The intensity of the rainfall continues to climb into June, but May’s wet spell signals the onset of the rainy season, characterized by more frequent and heavier downpours. As the month progresses, the lush landscape of Ha Long becomes even more vibrant, creating a stunning backdrop of greenery set against its iconic limestone karsts. However, visitors should be prepared for the increased humidity and the likelihood of rain, which adds to the region's tropical charm.
In May, Ha Long, Vietnam experiences a notable rise in humidity, reaching 73%. This increase aligns with the overall trend of escalating humidity levels as the region transitions into the summer months. Following a dip in April, where humidity was at a lower 64%, May signals the beginning of a more humid season, with levels steadily intensifying through June and July, where they peak at around 90%. This pattern highlights the tropical climate’s shift, with humidity creeping upward from spring to summer, inviting lush landscapes and vibrant marine life to thrive in the balmy air of Ha Long Bay.
In May, Ha Long, Vietnam, experiences an extreme UV Index of 13, mirroring the trend seen in April and the upcoming summer months. With a burn time of just 10 minutes, it's crucial for visitors to take extra precautions against intense sun exposure. This period marks the continuation of a pattern where the UV Index reaches its peak, indicating that outdoor enthusiasts should wear protective clothing and apply sunscreen regularly. As temperatures rise and the sun’s rays become increasingly potent, understanding the UV Index is vital for enjoying the stunning beauty of Ha Long safely. For more details, visit the Ha Long UV Index page.
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May brings a radiant transformation to Ha Long, Vietnam, as the region basks in an impressive 307 hours of sunshine—its brightest month of the year. This notable increase from April's 248 hours highlights a shift into the sun-soaked summer season. Following the peak in May, sunshine levels remain generous through June and July, with nearly 300 hours of sunlight each month, making for ideal beach days and spectacular views of the iconic karst landscapes. As the summer wanes into August, a gentle decline to 266 hours reminds visitors that even as the days shorten, the charm of Ha Long remains unyielding. With abundant sunshine throughout spring and early summer, May marks not just a peak in hours, but the start of an adventure-filled season in this breathtaking destination.
In Ha Long, Vietnam, the likelihood of sunny weather in May stands at 31%, which reflects a moderate chance amidst the region's shifting seasons. As spring gives way to summer, the sun begins to make its presence felt; however, May's sun chances are notably higher than the preceding months like April (20%) and March (24%). This month acts as a transitional period, offering a glimpse of sunnier days ahead before the rainier months of June (14%) and July (23%) arrive. While May may not be the sunniest month, it certainly serves as a beacon of brighter days, contrasting sharply with the gloomier tendencies of the late summer.
In Ha Long, Vietnam, daylight duration reveals a captivating seasonal pattern that enhances the allure of this coastal paradise. As January unfolds, the sun graciously graces the skies for about 10 hours, gradually increasing to 11 hours in February. By March, the days stretch to a delightful 12 hours, a trend that continues into April. This bloom of daylight reaches its peak in May, offering 13 hours of sunlight, making it an ideal time for exploration and adventure. The daylight remains generous throughout June and July, consistently providing 13 hours of sunshine. However, as summer wanes into August, the daylight begins its slow descent back to 12 hours, continuing this gradual decline into the cooler months of September and October. By the end of the year, daylight dips back to 11 hours in November and finally returns to 10 hours in December, completing a beautiful cycle that reflects the rhythm of nature in this vibrant region.
In Ha Long, Vietnam, May brings a delightful increase in wind speed, averaging 3.7 m/s (8 mph), making it one of the breezier months of the year. As spring transitions to summer, the winds begin to pick up, following a gradual ascent from 2.5 m/s in February to 3.0 m/s in April. This upward trend peaks in May and June, before slightly decreasing in the hotter months of July and August, which reflect a more moderate 2.7 m/s (6 mph). Interestingly, the wind speeds take another leap in October, highlighting the dynamic shifts in weather patterns throughout the year. Ultimately, May's gentle winds enhance the enchanting atmosphere of Ha Long Bay, inviting visitors to enjoy a blend of soft breezes and stunning seascapes.
Weather in Ha Long varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Ha Long, focusing on differences in temperature, rainfall, humidity, and UV levels.
May and January present strikingly different weather patterns, with May being significantly warmer and more humid. In May, temperatures range from a minimum of 19°C (66°F) to a scorching maximum of 36°C (98°F), accompanied by an average temperature of 27°C (81°F). This month also sees considerable rainfall, with 184 mm (7.2 in) of precipitation over 19 days, leading to a humidity level of 73%. In contrast, January offers a much cooler climate, with temperatures ranging from a minimum of 8°C (46°F) to a maximum of 26°C (80°F) and an average temperature of 18°C (64°F). Rainfall is minimal in January, totaling just 28 mm (1.1 in) over 5 days, and the humidity is slightly lower at 66%. For more specific weather details, you can check Ha Long weather in January.
In comparing the weather of May and February, it’s clear that May is significantly warmer and wetter. The average temperature in May reaches around 27°C (81°F), with maximums soaring to 36°C (98°F), while February’s averages sit at a cooler 18°C (65°F) with a maximum of 27°C (80°F). Additionally, May experiences considerable rainfall, totaling 184 mm (7.2 in) over 19 days, compared to February's much lighter precipitation of 36 mm (1.4 in) across just 7 days. The humidity remains relatively similar in both months, with May at 73% and February at 71%. For more detailed insights, you can check the Ha Long weather in February.
In comparing the weather of May and March, it is evident that May tends to be significantly warmer. While March experiences minimum temperatures around 14°C (57°F) and averages of 21°C (71°F), May sees minimums of 19°C (66°F) and averages soaring to 27°C (81°F). Additionally, May can reach maximum temperatures of 36°C (98°F), compared to March's peak of 31°C (88°F).
When it comes to precipitation, March is generally drier, with only 52 mm (2.0 in) of rainfall across 15 days, whereas May can be quite rainy with 184 mm (7.2 in) in 19 days. Interestingly, the humidity levels in both months are fairly similar, with May at 73% and March slightly lower at 69%. For more specific details on March weather, you can check Ha Long weather in March.
In comparing the weather between April and May, it's clear that May is significantly warmer, with average temperatures rising from 24°C (75°F) in April to 27°C (81°F) in May. Additionally, the maximum temperatures in May reach up to 36°C (98°F), compared to 33°C (91°F) in April. However, May also sees a considerable increase in precipitation, with 184 mm (7.2 in) of rain over 19 days, compared to just 91 mm (3.6 in) over 15 days in April. The humidity is also higher in May at 73%, compared to 64% in April, making the atmosphere feel more humid and heavy. For more specific information regarding the weather conditions in Ha Long during April, visit Ha Long weather in April.
May and June both exhibit warm temperatures, but June tends to be slightly hotter and more humid. In May, temperatures range from a minimum of 19°C (66°F) to a maximum of 36°C (98°F) with an average of 27°C (81°F). In contrast, June sees temperatures starting at a minimum of 23°C (74°F) and reaching up to 38°C (100°F), with an average of 30°C (86°F). Precipitation is also higher in June, totaling 240 mm (9.4 in), compared to May's 184 mm (7.2 in), and June experiences more humid conditions at 81% humidity versus May's 73%. For a more detailed look at weather patterns, check out Ha Long weather in June.
May and July exhibit notable differences in weather patterns, particularly in temperature and humidity. May typically sees temperatures ranging from a minimum of 19°C (66°F) to a maximum of 36°C (98°F), with an average of 27°C (81°F). In contrast, July's temperatures are generally warmer, with a minimum of 25°C (77°F), an average of 29°C (85°F), and the same maximum of 36°C (98°F). Precipitation is significantly higher in July, accumulating 287 mm (11.3 in) over 24 days, compared to May's 184 mm (7.2 in) over 19 days. The humidity also rises in July to 90%, making it a more humid month overall. For more details, you can check Ha Long weather in July.
Comparing the weather between May and August reveals distinct differences in both temperature and precipitation patterns. In May, temperatures range from a minimum of 19°C (66°F) to a maximum of 36°C (98°F), with an average of 27°C (81°F) and a moderate humidity of 73%. However, this month experiences significant rainfall, totaling 184 mm (7.2 in) over 19 days. In contrast, August features generally higher temperatures, with a minimum of 24°C (76°F) and an average of 28°C (83°F), while still reaching a maximum of 36°C (97°F). The humidity also rises to 89%, and the month sees a substantial increase in precipitation, with 521 mm (20.5 in) over 28 rainy days. For a more detailed understanding of weather conditions in August, you can visit Ha Long weather in August.
In comparing the weather between May and September, May tends to be slightly milder with temperatures ranging from a minimum of 19°C (66°F) to a maximum of 36°C (98°F), while September sees a slightly warmer minimum of 22°C (72°F) and a maximum of 35°C (95°F). Precipitation is notably higher in September, with 256 mm (10.1 in) over 23 days compared to May's 184 mm (7.2 in) over 19 days, reflecting increased rainfall during the latter month. Additionally, humidity levels rise from 73% in May to a more humid 82% in September, making the latter feel stickier. For a detailed look at September's weather specifically, you can check Ha Long weather in September.
May and October both feature warm temperatures, but October tends to be slightly cooler with average highs of 25°C (77°F) compared to May's 27°C (81°F). In terms of extremes, May can reach maximum temperatures of up to 36°C (98°F) while October's peak is 34°C (94°F). Both months are prone to precipitation, with October receiving 204 mm (8.0 in) over 16 days, while May sees slightly less total rainfall at 184 mm (7.2 in) over 19 days. Humidity levels are similar, with October at 77% and May at 73%. For a more detailed look at October's weather in Ha Long, check Ha Long weather in October.
In comparison, May features much warmer temperatures with a minimum of 19°C (66°F) and an average of 27°C (81°F), peaking at 36°C (98°F). It is also significantly wetter, with 184 mm (7.2 in) of rainfall spread across 19 days, resulting in high humidity at 73%. In contrast, November experiences cooler conditions, with a minimum of 12°C (54°F) and an average temperature of 22°C (73°F), reaching a maximum of 30°C (86°F). The month sees considerably less precipitation, totaling just 43 mm (1.7 in) over 9 days, and maintains a similar humidity level at 72%. For more details on November weather, visit Ha Long weather in November.
May and December present contrasting weather patterns. In May, temperatures soar with a minimum of 19°C (66°F) and peak at a scorching 36°C (98°F), creating a warm average of 27°C (81°F). Additionally, May is characterized by significant rainfall, totaling 184 mm (7.2 in) over 19 days, coupled with a high humidity level of 73%. In contrast, December offers a cooler climate, with temperatures ranging from a minimum of 8°C (46°F) to a maximum of 28°C (82°F), resulting in a more moderate average of 18°C (66°F). December sees much less rain, accumulating only 31 mm (1.2 in) over 6 days, and maintains a slightly lower humidity of 71%. For a detailed look at December weather, visit Ha Long weather in December.
As May unfolds in Ha Long, the weather marks a notable shift towards warmer and more humid conditions compared to earlier months. With temperatures soaring up to 36°C (98°F) and an average of 27°C (81°F), this month welcomes visitors with balmy days perfect for exploration. However, expect frequent rain, as the precipitation extends over 19 days, contributing to a lush, vibrant landscape. The humidity level stays notably high at 73%, making it essential to stay hydrated and seek shade during peak hours. For a comprehensive understanding of Ha Long’s climate, explore our detailed guide on Ha Long Climate.