Last updated: January 18, 2025
Vientiane, the vibrant capital of Laos, experiences a distinct tropical climate classified under the Köppen-Geiger system as Cwa and Aw. The city’s temperature ranges from a crisp 2°C (36°F) in December, marking the cooler months, to an intense 41°C (107°F) in May, during the peak of summer heat. On average, Vientiane enjoys a pleasant 24°C (76°F), allowing for diverse climatic experiences throughout the year, from mild winters to sweltering summers.
In Vientiane, Laos, temperature patterns exhibit a clear seasonal trend marked by warm to hot conditions throughout the year. The winter months of December and January see lower temperatures, with minimums dropping to 2°C (36°F) and 6°C (42°F), respectively, while daytime averages remain mild, around 20°C (69°F) to 21°C (70°F). As the city transitions into the dry season, February and March bring a gradual increase, with maximums peaking at 37°C (99°F) and 39°C (102°F), setting the stage for the sweltering summer months of April and May, which reach highs of 41°C (107°F). The arrival of the wet season in June, July, and August ushers in slightly cooler averages, consistently around 26°C (79°F), despite maximum temperatures remaining high, fluctuating between 36°C (97°F) and 38°C (101°F). By the time autumn arrives in September and October, a gradual cooling can be felt, with temperatures returning to more moderate levels, ultimately giving way to the cooler months of November and December, thus completing a dynamic and varied climatic cycle.
Muang Phon-Hong experiences a temperature range from a minimum of 9°C (48°F) in December to a scorching maximum of 41°C (107°F) in May, showcasing a significant variation throughout the year monthly temperatures in Muang Phon-Hong. Meanwhile, Muang Kasi records a chilly low of 2°C (36°F) in December, rising to a comfortable maximum of 34°C (94°F) in April monthly temperatures in Muang Kasi. Vangviang presents a minimum of 4°C (39°F) in December and peaks at 37°C (98°F) in April, illustrating a mild climate overall monthly temperatures in Vangviang.
Precipitation in Vientiane, Laos, exhibits a pronounced seasonal variation, with the majority of rainfall concentrated during the monsoon months from May to August. Beginning with January and February, the city experiences relatively low rainfall, peaking at 18 mm (0.7 in) and 28 mm (1.1 in) respectively, accompanied by only a few days of rain. As the dry season transitions into wetter weather, March sees a notable increase to 45 mm (1.8 in), setting the stage for the onset of the monsoon.
From April onward, Vientiane witnesses a dramatic surge in precipitation, with April receiving 105 mm (4.1 in), escalating to the peak rainfall month of August, which records an impressive 508 mm (20.0 in). This wet season is characterized by frequent rainfall, with July and August experiencing the highest number of rainy days, averaging 28 days each month. Following the monsoon, rainfall tapers off significantly in September and October, with totals of 287 mm (11.3 in) and 156 mm (6.1 in), respectively, before returning to drier conditions in November and December.
In Vientiane, Laos, the sunshine duration demonstrates a compelling seasonal trend, showcasing a gradual increase during the early months of the year, peaking in March with 317 hours of sunshine. January and February lay the groundwork for this upward trajectory, with 248 hours and 292 hours respectively. As spring unfolds and transitions into the summer, the number of sunshine hours remains consistently high, fluctuating around the 300-hour mark in April and May. Despite the onset of the wet season in June, which sees a decrease to 266 hours, the pattern of significant sunshine remains evident through July and August, although these months experience a dip due to increased cloud cover and precipitation.
As the weather shifts back to drier conditions in the latter part of the year, sunshine duration picks up again, with noteworthy outcomes in September, October, and November. September sees an increase to 273 hours, and by October, the sunshine duration rebounds to 293 hours. Moving into the end of the year, November and December are marked by impressive sunshine totals of 303 and 309 hours respectively, offering several bright days amid the cooler temperatures. Overall, Vientiane enjoys a rich abundance of sunshine throughout the year, particularly in the early spring and late autumn, making it an appealing destination for sun-seekers.
The UV Index in Vientiane, Laos, exhibits a striking pattern throughout the year, characterized by high to extreme values that signify the need for sun protection. Beginning in January, the UV Index stands at 9, categorized as very high, with a burn time of just 15 minutes. As the year progresses, the UV levels escalate dramatically, peaking in July and August with an impressive 15 on the scale, both classified as extreme, necessitating protective measures within just 10 minutes of sun exposure. This trend continues into the fall, where values remain similarly elevated, indicating that residents and visitors should be vigilant against overexposure.
The months from February to May consistently record extreme UV Index values ranging from 12 to 14, reinforcing the importance of sun safety practices during this time. Though the intensity of UV radiation begins to subside slightly in November and December, with levels returning to 10 and 9 respectively, the need for sun protection remains critical, given the high burn times in all months. Overall, the UV Index in Vientiane serves as a reminder of the considerable solar exposure inherent to the region, suggesting that caution and appropriate adaptations are essential year-round to mitigate UV-related health risks.
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In Vientiane, Laos, daylight duration shows a relatively stable pattern throughout the year, with minor variations across the seasons. From January to February, the city enjoys approximately 11 hours of daylight, providing consistent light during the cooler months. As the days gradually lengthen, March through May sees an increase in daylight hours, maintaining a steady 12 hours from March to May. This transition marks the arrival of warmer temperatures, contributing to the region's tropical climate.
As the wet season approaches, daylight extends further to 13 hours during June and July, offering ample time for outdoor activities. Following this peak, daylight begins to decrease again, returning to 12 hours in August and September, and tapering off to 11 hours from October through December. This cyclical pattern emphasizes Vientiane's equatorial positioning, resulting in relatively consistent daylight year-round, thus supporting a variety of cultural and agricultural activities while providing a predictable rhythm to daily life.
Muang Kasi, Laos experiences a tropical climate with distinct wet and dry seasons. Temperatures range from a chilly 2°C (36°F) in December to a warm peak of 34°C (93°F) in April and May. Rainfall is substantial, particularly from June to August when monthly precipitation can exceed 600 mm (23.6 in). Despite the high humidity during the rainy season, the area enjoys a significant amount of sunshine throughout the year, with the most hours recorded in March (316 hours). For more detailed information, visit Muang Kasi climate.
The climate in Muang Phon-Hong, Laos, is characterized by a warm tropical pattern with distinct wet and dry seasons. Temperatures range from a minimum of 9°C (48°F) in December to a peak of 41°C (107°F) in May, with an annual average around 28°C (82°F). Rainfall is abundant, especially from May to August, with June and July receiving the highest precipitation of over 400 mm. The region enjoys plenty of sunshine, particularly in the early months of the year, with January averaging 250 hours. For more detailed information, visit Muang Phon-Hong climate.
Muang Sanakham, Laos, experiences a tropical climate characterized by hot temperatures and distinct wet and dry seasons. From January to March, temperatures range from a minimum of 10°C (50°F) to a maximum of 39°C (102°F), with increasing precipitation starting in February. The monsoon season peaks from May to August, with July recording the highest rainfall at 233 mm (9.2 in). Despite the heavy rain, sunshine remains abundant, especially in the earlier months, with March enjoying up to 322 hours of sunlight. For more details, visit Muang Sanakham climate.
Vangviang, Laos experiences a tropical climate characterized by warm temperatures and distinct wet and dry seasons. From January to March, temperatures gradually rise, peaking in April with a maximum of 37°C (98°F) and minimal rainfall. The monsoon season starts in May, with heavy rains peaking in July and August, accumulating over 500 mm (20 in) per month. Despite the rain, sunshine hours are significant, with March boasting the highest at 316 hours. For more details, visit Vangviang climate.
In summary, Vientiane, Laos, presents a dynamic climate characterized by distinct temperature patterns, varying precipitation, substantial sunshine duration, elevated UV indexes, and consistent daylight hours throughout the year. The city's tropical climate reveals warm to hot temperatures, peaking during the summer months, while the wet season brings significant rainfall and cloud cover, contrasted by periods of abundant sunshine, especially in the spring and late autumn. Additionally, the high UV index underscored the importance of sun safety across the year, particularly during the extreme months. Together, these climatic factors not only shape the daily lives of those in Vientiane but also create a vibrant environment for agriculture, tourism, and cultural activities, highlighting the intricate balance of weather and climate in this beautiful Southeast Asian capital.