Last updated: August 21, 2025
In May, Vientiane experiences a warm and humid climate, with maximum temperatures soaring up to 41°C (107°F), making it one of the hottest months of the year. The average temperature hovers around a balmy 29°C (85°F), while the evenings bring a slight respite with a minimum of 22°C (71°F). Rainfall is significant, with a total precipitation of 204 mm (8.0 in) spread across 21 rainy days, contributing to the region's lush greenery. With an average humidity level of 69%, visitors can expect a muggy atmosphere, ideal for discovering the vibrant culture of Laos amidst the tropical backdrop.
In May, Vientiane experiences a warm transition into the peak of summer, with minimum temperatures rising to 22°C (71°F), while average daily highs hover around 41°C (107°F). This month marks a noticeable escalation from the cooler early months of the year, following April's highs of 42°C (107°F). With an average of 29°C (85°F), the temperature remains consistent yet toasty, reflecting a trend towards higher heat as the monsoon season approaches. Although the evenings cool slightly, the overall warmth combined with humidity signals the onset of the wet season, inviting both locals and travelers to enjoy balmy nights and vibrant outdoor activities before the rains arrive.
In May, Vientiane experiences a significant leap in rainfall, with 204 mm (8.0 in) pouring down over 21 days. This stark increase marks the beginning of the monsoon season, as the city transitions from the drier months of April's 70 mm (2.8 in) to the lush, wet conditions that will prevail in the following months. The rainfall during May showcases a drastic shift, almost tripling compared to April and laying the groundwork for June's even heavier deluges. As the rain transforms the landscape, the vibrant greenery that defines this season begins to flourish, creating a stunning backdrop as Vientiane embraces the heart of its wet season.
As Vientiane transitions into May, the weather takes a notable turn, with humidity levels climbing to 69%. This increase marks a significant rise from the drier months of March and April, where humidity sat at just 39% and 40%, respectively. May serves as a precursor to the sweltering monsoon season, which kicks in during the following months. By June, humidity spikes dramatically to 81% and continues to escalate, peaking in the summer months, with August reaching a muggy 87%. This trend highlights the shift from the cooler, more comfortable early months of the year to the increasingly humid conditions typical of Laos's tropical climate, emphasizing the importance of preparing for the impending heat and moisture.
In May, Vientiane experiences an extreme UV Index of 14, maintaining high levels of sun exposure that began in February and continue through the early summer months. With a swift burn time of just 10 minutes, it's crucial for residents and visitors alike to take protective measures against the sun's harmful rays. Following closely in June, the UV Index remains at 13, while July through September sees a steady 14, illustrating the persistent intensity of sunlight during this period. As the year transitions towards October, the UV Index gradually declines to 12, yet still demands caution. Overall, May stands out as a peak time for UV exposure in Vientiane, making it essential to stay informed and protected. For more details on the UV Index and its implications, visit Vientiane UV Index.
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In May, Vientiane basks in a delightful 309 hours of sunshine, mirroring the sunshine levels from April and hinting at the tail end of the dry season. As spring blossoms into early summer, the city enjoys a consistent brightness that has been steadily increasing since January. The sunshine peaks in March with 318 hours, indicating a vibrant lead-up to May, but the prevailing warmth of the preceding months sets the stage for bright days ahead. Following May, the sunshine starts to dip in June and July, a gentle reminder of the approaching rainy season. Overall, the trend highlights a gradual ascent of sunny hours leading into mid-year, creating a beautiful backdrop for both residents and visitors alike.
As May unfolds in Vientiane, Laos, the likelihood of sunny weather dips to 38%, marking a significant decrease from earlier months. This trend is noticeable when comparing May's sunshine potential to the bright sunshine typical of January and February, which enjoy probabilities of 82% and 87% respectively. However, by the time we reach April, the chances drop sharply to 29%, foreshadowing the cloudier days ahead. Following May, the situation worsens, with June and July seeing a mere 13% to 15% chance of sun. This gradual decline not only highlights the transitional nature of Vientiane’s climate but also suggests that those seeking sunny adventures should plan their travels for earlier in the year to make the most of the abundant sunshine.
In Vientiane, Laos, the daylight duration reflects a distinct seasonal rhythm. From January to April, the city enjoys a consistent 11 to 12 hours of sunlight, offering a gentle transition as spring approaches. As May arrives, daylight holds steady at 12 hours before extending into the longer days of June and July, which bask in 13 hours of sunshine—the peak of the year’s brightness. Following this vibrant mid-year phase, daylight gradually tapers back in the latter months, settling into 11 hours by October and remaining stable through December. This pattern beautifully captures the essence of tropical living, where daylight duration fluctuates gently, inviting both relaxation and rejuvenation throughout the year.
In May, the wind in Vientiane, Laos, tends to be gentle, with an average speed of 1.3 m/s (3 mph). This marks a noticeable decline from the slightly brisker speeds experienced earlier in the year, particularly in January and February, where winds averaged 2.0 m/s (4 mph). As the dry season transitions into the wet months, wind speeds generally hover around 1.3 to 1.8 m/s (3 to 4 mph), indicating a trend of mild breezes that provide a refreshing respite from the burgeoning heat. This pattern continues into June and beyond, with the city experiencing only modest fluctuations in wind speed, fostering a serene atmosphere perfect for outdoor exploration.
Weather in Vientiane varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Vientiane, focusing on differences in temperature, rainfall, humidity, and UV levels.
May and January present starkly contrasting weather conditions. In May, temperatures soar with a minimum of 22°C (71°F) and an average of 29°C (85°F), peaking at a scorching 41°C (107°F). The month witnesses significant rainfall, with 204 mm (8.0 in) spread over 21 days, and the humidity levels are quite high at 69%. In contrast, January offers much milder weather, with temperatures ranging from a minimum of 10°C (51°F) to a comfortable average of 24°C (75°F), and a maximum of 35°C (95°F). Precipitation is minimal during this month, totaling just 6 mm (0.2 in) over only one day, and humidity sits at a more moderate 52%. For a detailed look at January's weather patterns, you can explore Vientiane weather in January.
When comparing the weather of February and May, it’s clear that May is significantly warmer and wetter. In May, temperatures range from a minimum of 22°C (71°F) to a sweltering maximum of 41°C (107°F), with an average of 29°C (85°F). In contrast, February enjoys milder temperatures, with a minimum of 13°C (55°F), an average of 25°C (76°F), and a maximum of 38°C (100°F). Additionally, May experiences much more rainfall, with 204 mm (8.0 in) spread over 21 days, compared to February’s meager 17 mm (0.7 in) on just 1 day. Humidity levels also differ, with May reaching 69%, while February remains cooler and drier at 49%. For more details on February weather, you can visit Vientiane weather in February.
In comparing the weather between March and May, we see noticeable differences. March tends to be milder, with temperatures ranging from a minimum of 17°C (63°F) to an average of 28°C (82°F), peaking at 40°C (104°F). It also experiences significantly less rainfall, with only 41 mm (1.6 in) over about six days, accompanied by a lower humidity of 39%. In contrast, May brings higher temperatures, with a minimum of 22°C (71°F) and an average of 29°C (85°F), reaching up to 41°C (107°F). This month also sees a substantial increase in precipitation, totaling 204 mm (8.0 in) across 21 days, along with higher humidity levels at 69%. For those looking for more detailed insights, you can check Vientiane weather in March.
In comparing the weather between April and May, both months exhibit similar average temperatures of 29°C (85°F); however, May experiences notably higher minimum and maximum temperatures, ranging from 22°C (71°F) to 41°C (107°F), compared to April's 17°C (63°F) to 42°C (107°F). Precipitation levels in May are significantly elevated, with 204 mm (8.0 in) spread over 21 days, contrasting sharply with April's 70 mm (2.8 in) over just 11 days. Additionally, May's humidity is higher at 69%, while April has a more comfortable 40%. For more detailed insights into April's weather, you can visit Vientiane weather in April.
May and June weather in Vientiane shows some notable differences. In May, temperatures range from a minimum of 22°C (71°F) to a maximum of 41°C (107°F), with an average of 29°C (85°F). The month is marked by significant precipitation, totaling 204 mm over 21 days and a humidity level of 69%. In contrast, June sees slightly warmer minimum temperatures at 24°C (75°F) while the maximum temperature decreases to 39°C (102°F), maintaining the same average of 29°C (85°F). However, June experiences increased rainfall of 309 mm spread over 25 days, accompanied by higher humidity at 81%. For further details, you can check Vientiane weather in June.
In May, temperatures in Vientiane can soar with minimums around 22°C (71°F) and maximums reaching up to 41°C (107°F). The weather is characterized by significant precipitation, totaling 204 mm (8.0 in) over 21 days, alongside a humidity level of 69%. In contrast, July sees a slightly higher minimum temperature of 25°C (76°F), with a more moderate maximum of 37°C (99°F) and an average temperature of 29°C (84°F). However, July is notably wetter, experiencing 331 mm (13.0 in) of rainfall over 26 days and higher humidity at 83%. For a detailed look at the weather specifics, check out Vientiane weather in July.
The weather in May and August presents notable differences in temperature and precipitation. In May, temperatures range from a minimum of 22°C (71°F) to a maximum of 41°C (107°F), with an average of 29°C (85°F). The month sees significant rainfall of 204 mm (8.0 in) distributed over 21 days and a humidity level of 69%. In contrast, August experiences slightly warmer temperatures with a minimum of 24°C (75°F) and an average of 28°C (83°F), peaking at 37°C (98°F). However, it is also the wettest month, with 402 mm (15.8 in) of rain over 26 days and higher humidity at 87%. For more detailed weather patterns, check Vientiane weather in August.
In the comparison of May and September weather, May tends to be hotter with average temperatures reaching 29°C (85°F) and a maximum of 41°C (107°F). In contrast, September sees slightly cooler temperatures, averaging 28°C (83°F) with a maximum of 37°C (98°F). However, September experiences higher precipitation levels, with 265 mm (10.4 in) over 24 days compared to May's 204 mm (8.0 in) over 21 days. Additionally, September has a higher humidity level at 86%, compared to May's 69%, making it feel more muggy during that month. For more specifics on September weather, you can check Vientiane weather in September.
In comparing the weather between May and October, it is evident that May tends to be warmer, with average temperatures reaching 29°C (85°F) and maximums soaring up to 41°C (107°F). In contrast, October experiences slightly cooler average temperatures at 28°C (82°F) and maximums of 36°C (98°F). Precipitation is notably higher in May, with 204 mm (8.0 in) over 21 days, compared to October's 129 mm (5.1 in) over 15 days. Additionally, October carries higher humidity levels at 74%, whereas May sits at 69%. For more detailed information on October weather, you can refer to Vientiane weather in October.
May and November present strikingly different weather patterns. In May, temperatures can soar, with minimums around 22°C (71°F) and maximums reaching up to 41°C (107°F), accompanied by high humidity at 69%. This month also sees considerable rainfall, averaging 204 mm (8.0 in) over 21 days. In contrast, November offers a more moderate climate, with minimum temperatures of 17°C (63°F) and maximums peaking at 36°C (98°F). The month is notably drier, receiving just 10 mm (0.4 in) of rain over only 3 days and slightly lower humidity at 63%. For more details, you can check Vientiane weather in November.
In May, the weather is characterized by high temperatures, with a minimum of 22°C (71°F) and an average of 29°C (85°F), reaching maximums up to 41°C (107°F). The month is also quite humid, with a humidity level of 69% and significant rainfall, totaling 204 mm (8.0 in) over 21 days. In contrast, December offers a much cooler climate, with temperatures ranging from a minimum of 9°C (48°F) to a comfortable average of 23°C (74°F), and highs reaching 35°C (95°F). Rainfall is minimal during this month, with only 7 mm (0.3 in) over just one day, and humidity levels drop to 57%. For more specific details about the weather in December, check out Vientiane weather in December.
As May unfolds in Vientiane, it signals a noticeable transition in weather, characterized by rising temperatures and increased humidity compared to earlier months. The city experiences its warmest days of the year, with soaring highs that can reach up to a sweltering 41°C (107°F), compelling locals and visitors alike to seek respite from the heat. This month also ushers in a higher frequency of rainfall, with around two-thirds of May days seeing some precipitation, contributing to a total that can accumulate to 204 mm. While the humidity hovers around 69%, it adds to the tropical ambiance, making it essential for travelers to stay hydrated and seek shade during the hottest hours. To explore more about this intriguing climate, check out Vientiane Climate.