Climate Insights for Vientiane

The climate in Vientiane is hot. The average annual temperature is 27°C and approximately 2038mm of precipitation falls per year. August is the wettest month, receiving around 513mm of rainfall. Vientiane is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: April, March, May. The coldest months are December, February, January, when temperatures can drop to 17°C.

Vientiane sees moderate temperature variation throughout the year, ranging from 17°C to 36°C. April is the hottest month, with daytime highs reaching 36°C and an average of 29°C. December is the coolest month, with minimum temperatures around 17°C and an average of 23°C. On average, daily temperatures fluctuate by about 9°C between overnight lows and afternoon highs. The sharpest temperature change occurs between February and March, with a 3°C shift in average temperatures.

Vientiane is a very wet location, receiving approximately 2038mm of precipitation annually, which averages out to around 170mm per month. The wettest month is August, averaging 513mm of rainfall. July and June also tend to see above-average precipitation. The driest month is December, with just 8mm. That's 505mm less than August, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.

Vientiane is relatively calm, with an average annual wind speed of 1km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is February, averaging 2km/h, though still comfortable for most outdoor activities. The calmest conditions occur in September, with average winds dropping to 1km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 1km/h gap between the calmest and windiest months.

It is currently summer in Vientiane, which began on June 21, 2026. Vientiane is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in April at around 36°C, while the coldest stretch bottoms out in December near 17°C. Autumn is next, beginning on September 23, 2026 — 93 days from now.

The best time to visit Vientiane is during January, February and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 23°C with modest rainfall averaging 14mm per month. By contrast, April can be uncomfortably hot with temperatures reaching 36°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.

The table below shows monthly climate averages for Vientiane based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.