Yearly & Monthly weather - Vientiane, Laos

Water geysers around the memorial Patuxay Monument in Vientiane, Laos

The climate of Vientiane

The geographical position of Vientiane places it in the heart of Laos. Its climatic conditions are mirrored in the tropical wet and dry or savanna climate, otherwise known as the Köppen climate classification Aw. These climatic conditions mold the city's overall weather patterns throughout the year.

Throughout the year, Vientiane experiences warm temperatures. The value ranges from a low average of 16.4°C (61.5°F) in January to a high average of 34.3°C (93.7°F) in April. Climatological data indicates relative humidity stays above 66% throughout the year, reaching up to 84% in August, affirming a consistently humid environment.

A unique attribute of Vientiane's weather is the considerable variability in monthly rainfall. Rainfall is minimal in the initial months of the year, with January observing a low of 8mm (0.31"). This figure escalates drastically in the middle of the year, reaching its peak in August, a robust 335mm (13.19"). The number of rainfall days follows a similar pattern, starting with only one day in January, then extending to 21 days by August. Despite the high volumes of rainfall, the city receives generous sunshine hours ranging from 4.4h in August to 8.3h in December and a UV index always matching or exceeding eight, cautioning residents and visitors about potential sun exposure dangers.

The best time to visit Vientiane

Vientiane offers the most favorable weather conditions and temperatures to visitors in the late autumn transitioning into the winter. Specifically starting from November to February. This period is characterized by cool temperature ranges from 28.1°C (82.6°F) to 30.8°C (87.4°F). This time frame also offers the least rainfall, ranging from 3mm (0.12") to 78mm (3.07"), with the number of rainfall days not surpassing nine days, making it an ideal time for outdoor activities and sightseeing.

The worst time to visit Vientiane

The period from May to October could be challenging for visitors not accustomed to high humidity and heavy rainfall. During these months, the temperatures hover between 31.3°C (88.3°F) to 34.3°C (93.7°F). The period also marks the start of the monsoon season, and the city experiences its maximum rainfall from 246mm (9.69") in May to 335mm (13.19") in August, which is coupled with up to 21 rainfall days per month. This humid, wet weather might not be preferable for outdoor explorations and may restrict the travelling experience.

Spring weather in Vientiane

In Vientiane, spring extends from March to May. This period observes an upward trend in temperatures, starting from 33°C (91.4°F) in March and peaking at 34.3°C (93.7°F) in April, before a small decrease down to 33°C (91.4°F) in May. Additionally, this period also spells the onset of the monsoon, as rainfall increases drastically from 34mm (1.34") in March to 246mm (9.69") in May. This transition period offers a blend of dry and wet climates, with increasing daylight hours from 12h in March to 13h in May.

Summer weather in Vientiane

The summer months in Vientiane, from June to August, bring high humidity levels and peak rainfall. Average temperatures during this period range from 31.3°C (88.3°F) to 30.8°C (87.4°F). Meanwhile, rainfall jumps further from 280mm (11.02") in June to a staggering high of 335mm (13.19") in August. These heavy showers increase the humidity, hovering between 82% to 84%, consecutively making this period the wettest season of the year.

Autumn weather in Vientiane

Autumn in Vientiane, observed from September to November, is characterized by a steady decrease in temperatures and rainfall. Temperatures hover between 30.9°C (87.6°F) to 29.8°C (85.6°F), making the weather gradually comfortable. Rainfall sees a sharp decrease from 297mm (11.69") in September to only 11mm (0.43") in November, with the number of rainy days dropping from 17 to just two. Therefore, this period provides a sigh of relief after the heavy summer monsoon showers.

Winter weather in Vientiane

Winter, from December to February, hosts the coolest months in Vientiane, with average temperatures ranging from 28.1°C (82.6°F) to 30.3°C (86.5°F). In December, the city experiences the least amount of rainfall in the year, pegged at merely 3mm (0.12"), with January not far behind, boasting only 8mm (0.31"), providing plenty of opportunities to engage in outdoor activities. These cool, dry months make the winter season a popular choice for visitors seeking respite from cold winters in other parts of the world.

Weather in January

January, typically a dry month in Vientiane, Laos, experiences temperatures ranging from 16.4°C (61.5°F) to 28.4°C (83.1°F). Cooler than the ensuing February, it boasts a moderate UV index and is less humid. The relatively low humidity makes for comfortable conditions, while the lengthy daylight hours facilitate outdoor activities. Weather in January »

Weather in February

February witnesses a slight incline in temperatures compared to January, with the onset of a warmer season in Vientiane, Laos. This month also experiences a marginal increase in daylight hours from 11.2 to 11.6 hours and a relative humidity of 68%. Weather in February »

Weather in March

March in Vientiane, Laos experiences a significant rise in temperatures, signifying the transition into the hotter months of the year. This month sees average temperatures fluctuating between 21.5°C (70.7°F) and 33°C (91.4°F) and records a UV index of 12, which is the maximum for the year. Weather in March »

Weather in April

April brings about the highest average temperatures in Vientiane between 23.8°C (74.8°F) to 34.3°C (93.7°F) along with an increase in rainfall from 34mm (1.34") in March to 85mm (3.35"). It heralds the arrival of the monsoon season, paving the way for an uptick in humidity in the coming months. Weather in April »

Weather in May

The weather in May in Vientiane, Laos, continues to intensify, with relatively high temperatures and a considerable increase in rainfall from 85mm (3.35") in April to 246mm (9.69"). A marked increase in humidity accompanies this shift to the monsoon season, with the relative humidity reaching 78%. Weather in May »

Weather in June

As the year progresses, June sees a drop in the average hours of sunshine in Vientiane, Laos. Coupled with escalating rainfall from 246mm (9.69") in May to 280mm (11.02") and temperatures ranging between 24.9°C (76.8°F) and 31.9°C (89.4°F), the weather is notably humid. Weather in June »

Weather in July

July marks the midpoint of the year with an increment in rain in Vientiane, Laos. The shift from 280mm (11.02") in June to 272mm (10.71") entails higher levels of humidity, an 82% relative humidity. Despite the prevailing rains and the high humidity, the city remains bustling and active. Weather in July »

Weather in August

August in Vientiane, Laos, denotes the peak of the rainy and monsoon season with rainfall figures standing at 335mm (13.19"). With higher rainfall and a steady temperature hovering between 24.6°C (76.3°F) and 30.8°C (87.4°F), humidity rises, impacting overall comfort slightly. Weather in August »

Weather in September

September witnesses a reduction in the rainfall from 335mm (13.19") in August to a more manageable 297mm (11.69") in Vientiane, Laos. This drop in rainfall comes with a slight decrease in temperatures and relative humidity. The weather signals the impending arrival of the cooler months, which citizens anticipate eagerly. Weather in September »

Weather in October

October in Vientiane, Laos, marks the cessation of the monsoon season, leading to considerably less rainfall compared to September. Temperatures, however, remain steady between 22.9°C (73.2°F) and 30.8°C (87.4°F). The decrease in the frequency and intensity of rain showers lends itself to a more comfortable, less humid climate. Weather in October »

Weather in November

November commences the return of drier conditions and a drop in rainfall from 78mm (3.07") in October to 11mm (0.43"), with temperatures between 19.3°C (66.7°F) and 29.8°C (85.6°F) in Vientiane, Laos. The declining temperature and sustained drying trend give rise to a pleasant climate perfect for tourism. Weather in November »

Weather in December

December brings the year to a close with the lowest average rainfall of 3mm (0.12") and temperatures ranging from 16.7°C (62.1°F) to 28.1°C (82.6°F) in Vientiane, Laos. The climate is characterized by relatively cooler temperatures and less rain, marking the arrival of the region's winter season. Weather in December »

Updated: Aug 8, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

How many days does it rain?

In Vientiane, during the entire year, the rain falls for 118 days and collects up to 1661mm (65.39") of precipitation.

What is the least humid month?

With an average relative humidity of 66%, March is the least humid month.

When is the highest UV index?

The months with the highest UV index in Vientiane are March through September, with an average maximum UV index of 12.

What is the hottest time of year?

April, with an average high of 34.3°C (93.7°F) and a low of 23.8°C (74.8°F), signifies the warmest month of the year.

When are the longest days?

The month with the longest days is June, with an average of 13h and 12min of daylight.

What is the most humid month?

The most humid month is August, with an average relative humidity of 84%.

What is the wettest month?

The month with the most rainfall is August, when the rain falls for 21 days and typically aggregates up to 335mm (13.19") of precipitation.

What is the month with the least sunshine?

The month with the least sunshine is August, with an average of 4.4h of sunshine.

What is the coldest month?

Vientiane witnesses the coldest weather in December, with temperatures averaging a high of 28.1°C (82.6°F) and a low of 16.7°C (62.1°F).

What is the driest month?

December is the month with the least rainfall in Vientiane. Rain falls for 1 days and accumulates 3mm (0.12") of precipitation.

What is the month with the shortest days?

December has the shortest days of the year, with an average of 11h and 6min of daylight.

Is there Daylight Saving Time (DST)?

Vientiane does not observe Daylight Saving Time (DST). +07 timezone is used throughout the entire year.

What month has the most sunshine?

December has the most sunshine of the year, with an average of 8.3h of sunshine.

When is the lowest UV index?

December is the month with the lowest UV index, with an average maximum UV index of 8.

Today

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Long-term

Year J F M A M J J A S O N D

Average temperature
Vientiane, Laos

Average high temperature in January:
28.4°C
Average high temperature in February:
30.3°C
Average high temperature in March:
33°C
Average high temperature in April:
34.3°C
Average high temperature in May:
33°C
Average high temperature in June:
31.9°C

Average high temperature in July:
31.3°C
Average high temperature in August:
30.8°C
Average high temperature in September:
30.9°C
Average high temperature in October:
30.8°C
Average high temperature in November:
29.8°C
Average high temperature in December:
28.1°C

The warmest month (with the highest average high temperature) is April (34.3°C).
The month with the lowest average high temperature is December (28.1°C).

Average low temperature in January:
16.4°C
Average low temperature in February:
18.5°C
Average low temperature in March:
21.5°C
Average low temperature in April:
23.8°C
Average low temperature in May:
24.6°C
Average low temperature in June:
24.9°C

Average low temperature in July:
24.7°C
Average low temperature in August:
24.6°C
Average low temperature in September:
24.1°C
Average low temperature in October:
22.9°C
Average low temperature in November:
19.3°C
Average low temperature in December:
16.7°C

The month with the highest average low temperature is June (24.9°C).
The coldest month (with the lowest average low temperature) is January (16.4°C).

Average humidity
Vientiane, Laos

The month with the highest relative humidity is August (84%).
The month with the lowest relative humidity is March (66%).

Average rainfall
Vientiane, Laos

The wettest month (with the highest rainfall) is August (334.6mm).
The driest month (with the least rainfall) is December (2.5mm).

Average rainfall days
Vientiane, Laos

Average rainfall days in January:
1 days
Average rainfall days in February:
2 days
Average rainfall days in March:
4 days
Average rainfall days in April:
8 days
Average rainfall days in May:
15 days
Average rainfall days in June:
18 days

Average rainfall days in July:
20 days
Average rainfall days in August:
21 days
Average rainfall days in September:
17 days
Average rainfall days in October:
9 days
Average rainfall days in November:
2 days
Average rainfall days in December:
1 days

The month with the highest number of rainy days is August (21 days).
The months with the least rainy days are January and December (1 days).

Average daylight / Average sunshine
Vientiane, Laos

Average daylight in January:
11h and 1min
Average daylight in February:
11h and 4min
Average daylight in March:
12h and 0min
Average daylight in April:
12h and 4min
Average daylight in May:
13h and 0min
Average daylight in June:
13h and 1min

Average daylight in July:
13h and 1min
Average daylight in August:
12h and 4min
Average daylight in September:
12h and 1min
Average daylight in October:
11h and 4min
Average daylight in November:
11h and 2min
Average daylight in December:
11h and 1min

The month with the longest days is June (Average daylight: 13h and 12min).
The month with the shortest days is December (Average daylight: 11h and 6min).

Average sunshine in January:
8h and 1min
Average sunshine in February:
7h and 4min
Average sunshine in March:
7h and 0min
Average sunshine in April:
7h and 3min
Average sunshine in May:
6h and 4min
Average sunshine in June:
5h and 1min

Average sunshine in July:
4h and 5min
Average sunshine in August:
4h and 2min
Average sunshine in September:
4h and 4min
Average sunshine in October:
8h and 0min
Average sunshine in November:
7h and 5min
Average sunshine in December:
8h and 2min

The month with the most sunshine is December (Average sunshine: 8h and 18min).
The month with the least sunshine is August (Average sunshine: 4h and 24min).

Average UV index
Vientiane, Laos

The months with the highest UV index are March, April, May, June, July, August and September (UV index 12).
The month with the lowest UV index is December (UV index 8).

Climate and monthly weather forecastVientiane, Laos

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